Commit Graph

409 Commits

Author SHA1 Message Date
Tim Chase 25458cbef9 Limit the amount of dnode metadata in the ARC
Metadata-intensive workloads can cause the ARC to become permanently
filled with dnode_t objects as they're pinned by the VFS layer.
Subsequent data-intensive workloads may only benefit from about
25% of the potential ARC (arc_c_max - arc_meta_limit).

In order to help track metadata usage more precisely, the other_size
metadata arcstat has replaced with dbuf_size, dnode_size and bonus_size.

The new zfs_arc_dnode_limit tunable, which defaults to 10% of
zfs_arc_meta_limit, defines the minimum number of bytes which is desirable
to be consumed by dnodes.  Attempts to evict non-metadata will trigger
async prune tasks if the space used by dnodes exceeds this limit.

The new zfs_arc_dnode_reduce_percent tunable specifies the amount by
which the excess dnode space is attempted to be pruned as a percentage of
the amount by which zfs_arc_dnode_limit is being exceeded.  By default,
it tries to unpin 10% of the dnodes.

The problem of dnode metadata pinning was observed with the following
testing procedure (in this example, zfs_arc_max is set to 4GiB):

    - Create a large number of small files until arc_meta_used exceeds
      arc_meta_limit (3GiB with default tuning) and arc_prune
      starts increasing.

    - Create a 3GiB file with dd.  Observe arc_mata_used.  It will still
      be around 3GiB.

    - Repeatedly read the 3GiB file and observe arc_meta_limit as before.
      It will continue to stay around 3GiB.

With this modification, space for the 3GiB file is gradually made
available as subsequent demands on the ARC are made.  The previous behavior
can be restored by setting zfs_arc_dnode_limit to the same value as the
zfs_arc_meta_limit.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4345
Issue #4512
Issue #4773
Closes #4858
2016-07-25 15:26:38 -07:00
Tim Chase e6603b7c1f Fix sync behavior for disk vdevs
Prior to b39c22b, which was first generally available in the 0.6.5
release as b39c22b, ZoL never actually submitted synchronous read or write
requests to the Linux block layer.  This means the vdev_disk_dio_is_sync()
function had always returned false and, therefore, the completion in
dio_request_t.dr_comp was never actually used.

In b39c22b, synchronous ZIO operations were translated to synchronous
BIO requests in vdev_disk_io_start().  The follow-on commits 5592404 and
aa159af fixed several problems introduced by b39c22b.  In particular,
5592404 introduced the new flag parameter "wait" to __vdev_disk_physio()
but under ZoL, since vdev_disk_physio() is never actually used, the wait
flag was always zero so the new code had no effect other than to cause
a bug in the use of the dio_request_t.dr_comp which was fixed by aa159af.

The original rationale for introducing synchronous operations in b39c22b
was to hurry certains requests through the BIO layer which would have
otherwise been subject to its unplug timer which would increase the
latency.  This behavior of the unplug timer, however, went away during the
transition of the plug/unplug system between kernels 2.6.32 and 2.6.39.

To handle the unplug timer behavior on 2.6.32-2.6.35 kernels the
BIO_RW_UNPLUG flag is used as a hint to suppress the plugging behavior.

For kernels 2.6.36-2.6.38, the REQ_UNPLUG macro will be available and
ise used for the same purpose.

Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4858
2016-07-25 14:24:47 -07:00
Nikolay Borisov 2c6abf15ff Remove znode's z_uid/z_gid member
Remove duplicate z_uid/z_gid member which are also held in the
generic vfs inode struct. This is done by first removing the members
from struct znode and then using the KUID_TO_SUID/KGID_TO_SGID
macros to access the respective member from struct inode. In cases
where the uid/gids are being marshalled from/to disk, use the newly
introduced zfs_(uid|gid)_(read|write) functions to properly
save the uids rather than the internal kernel representation.

Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4685
Issue #227
2016-07-25 13:21:49 -07:00
Tom Caputi 0b04990a5d Illumos Crypto Port module added to enable native encryption in zfs
A port of the Illumos Crypto Framework to a Linux kernel module (found
in module/icp). This is needed to do the actual encryption work. We cannot
use the Linux kernel's built in crypto api because it is only exported to
GPL-licensed modules. Having the ICP also means the crypto code can run on
any of the other kernels under OpenZFS. I ended up porting over most of the
internals of the framework, which means that porting over other API calls (if
we need them) should be fairly easy. Specifically, I have ported over the API
functions related to encryption, digests, macs, and crypto templates. The ICP
is able to use assembly-accelerated encryption on amd64 machines and AES-NI
instructions on Intel chips that support it. There are place-holder
directories for similar assembly optimizations for other architectures
(although they have not been written).

Signed-off-by: Tom Caputi <tcaputi@datto.com>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4329
2016-07-20 10:43:30 -07:00
Gvozden Neskovic 26a08b5ca9 RAIDZ parity kstat rework
Print table with speed of methods for each implementation.
Last line describes contents of [fastest] selection.

Signed-off-by: Gvozden Neskovic <neskovic@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4860
2016-07-19 16:43:07 -07:00
Gvozden Neskovic c9187d867f Fixes and enhancements of SIMD raidz parity
- Implementation lock replaced with atomic variable

- Trailing whitespace is removed from user specified parameter, to enhance
experience when using commands that add newline, e.g. `echo`

- raidz_test: remove dependency on `getrusage()` and RUSAGE_THREAD, Issue #4813

- silence `cppcheck` in vdev_raidz, partial solution of Issue #1392

- Minor fixes and cleanups

- Enable use of original parity methods in [fastest] configuration.
New opaque original ops structure, representing native methods, is added
to supported raidz methods. Original parity methods are executed if selected
implementation has NULL fn pointer.

Signed-off-by: Gvozden Neskovic <neskovic@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4813
Issue #1392
2016-07-19 16:43:07 -07:00
Chris Dunlop dfbc86309f Use native inode->i_nlink instead of znode->z_links
A mostly mechanical change, taking into account i_nlink is 32 bits vs ZFS's
64 bit on-disk link count.

We revert "xattr dir doesn't get purged during iput" (ddae16a) as this is a
more Linux-integrated fix for the same issue.

In addition, setting the initial link count on a new node has been changed
from setting one less than required in zfs_mknode() then incrementing to the
correct count in zfs_link_create() (which was somewhat bizarre in the first
place), to setting the correct count in zfs_mknode() and not incrementing it
in zfs_link_create(). This both means we no longer set the link count in
sa_bulk_update() twice (once for the initial incorrect count then again for
the correct count), as well as adhering to the Linux requirement of not
incrementing a zero link count without I_LINKABLE (see linux commit
f4e0c30c).

Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Closes #4838
Issue #227
2016-07-14 16:25:34 -07:00
Gvozden Neskovic ae25d22235 Add RAID-Z routines for SSE2 instruction set, in x86_64 mode.
The patch covers low-end and older x86 CPUs.  Parity generation is
equivalent to SSSE3 implementation, but reconstruction is somewhat
slower.  Previous 'sse' implementation is renamed to 'ssse3' to
indicate highest instruction set used.

Benchmark results:
scalar_rec_p                    4    720476442
scalar_rec_q                    4    187462804
scalar_rec_r                    4    138996096
scalar_rec_pq                   4    140834951
scalar_rec_pr                   4    129332035
scalar_rec_qr                   4    81619194
scalar_rec_pqr                  4    53376668

sse2_rec_p                      4    2427757064
sse2_rec_q                      4    747120861
sse2_rec_r                      4    499871637
sse2_rec_pq                     4    522403710
sse2_rec_pr                     4    464632780
sse2_rec_qr                     4    319124434
sse2_rec_pqr                    4    205794190

ssse3_rec_p                     4    2519939444
ssse3_rec_q                     4    1003019289
ssse3_rec_r                     4    616428767
ssse3_rec_pq                    4    706326396
ssse3_rec_pr                    4    570493618
ssse3_rec_qr                    4    400185250
ssse3_rec_pqr                   4    377541245

original_rec_p                  4    691658568
original_rec_q                  4    195510948
original_rec_r                  4    26075538
original_rec_pq                 4    103087368
original_rec_pr                 4    15767058
original_rec_qr                 4    15513175
original_rec_pqr                4    10746357

Signed-off-by: Gvozden Neskovic <neskovic@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4783
2016-07-13 10:24:55 -07:00
Chunwei Chen 31b6111fd9 Kill zp->z_xattr_parent to prevent pinning
zp->z_xattr_parent will pin the parent. This will cause huge issue
when unlink a file with xattr. Because the unlinked file is pinned, it
will never get purged immediately. And because of that, the xattr
stuff will never be marked as unlinked. So the whole unlinked stuff
will stay there until shrink cache or umount.

This change partially reverts e89260a.  This is safe because only the
zp->z_xattr_parent optimization is removed, zpl_xattr_security_init()
is still called from the zpl outside the inode lock.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Issue #4359
Issue #3508
Issue #4413
Issue #4827
2016-07-12 14:18:10 -07:00
Igor Kozhukhov eca7b76001 OpenZFS 6314 - buffer overflow in dsl_dataset_name
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Igor Kozhukhov <ikozhukhov@gmail.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>

OpenZFS-issue: https://www.illumos.org/issues/6314
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/d6160ee
2016-06-28 13:47:03 -07:00
Brian Behlendorf 43e52eddb1 Implement zfs_ioc_recv_new() for OpenZFS 2605
Adds ZFS_IOC_RECV_NEW for resumable streams and preserves the legacy
ZFS_IOC_RECV user/kernel interface.  The new interface supports all
stream options but is currently only used for resumable streams.
This way updated user space utilities will interoperate with older
kernel modules.

ZFS_IOC_RECV_NEW is modeled after the existing ZFS_IOC_SEND_NEW
handler.  Non-Linux OpenZFS platforms have opted to change the
legacy interface in an incompatible fashion instead of adding a
new ioctl.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2016-06-28 13:47:03 -07:00
Andrew Stormont b607405fea OpenZFS 6536 - zfs send: want a way to disable setting of DRR_FLAG_FREERECORDS
Authored by: Andrew Stormont <astormont@racktopsystems.com>
Reviewed by: Anil Vijarnia <avijarnia@racktopsystems.com>
Reviewed by: Kim Shrier <kshrier@racktopsystems.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>

OpenZFS-issue: https://www.illumos.org/issues/6536
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/880094b
2016-06-28 13:47:03 -07:00
Paul Dagnelie e6d3a843d6 OpenZFS 6393 - zfs receive a full send as a clone
Authored by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Prakash Surya <prakash.surya@delphix.com>
Reviewed by: Richard Elling <Richard.Elling@RichardElling.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>

OpenZFS-issue: https://www.illumos.org/issues/6394
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/68ecb2e
2016-06-28 13:47:03 -07:00
Matthew Ahrens 47dfff3b86 OpenZFS 2605, 6980, 6902
2605 want to resume interrupted zfs send
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Richard Elling <Richard.Elling@RichardElling.com>
Reviewed by: Xin Li <delphij@freebsd.org>
Reviewed by: Arne Jansen <sensille@gmx.net>
Approved by: Dan McDonald <danmcd@omniti.com>
Ported-by: kernelOfTruth <kerneloftruth@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>

OpenZFS-issue: https://www.illumos.org/issues/2605
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/9c3fd12

6980 6902 causes zfs send to break due to 32-bit/64-bit struct mismatch
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Ported by: Brian Behlendorf <behlendorf1@llnl.gov>

OpenZFS-issue: https://www.illumos.org/issues/6980
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/ea4a67f

Porting notes:
- All rsend and snapshop tests enabled and updated for Linux.
- Fix misuse of input argument in traverse_visitbp().
- Fix ISO C90 warnings and errors.
- Fix gcc 'missing braces around initializer' in
  'struct send_thread_arg to_arg =' warning.
- Replace 4 argument fletcher_4_native() with 3 argument version,
  this change was made in OpenZFS 4185 which has not been ported.
- Part of the sections for 'zfs receive' and 'zfs send' was
  rewritten and reordered to approximate upstream.
- Fix mktree xattr creation, 'user.' prefix required.
- Minor fixes to newly enabled test cases
- Long holds for volumes allowed during receive for minor registration.
2016-06-28 13:47:02 -07:00
Brian Behlendorf 669cf0ab29 Sync DMU_BACKUP_FEATURE_* flags
Flag 20 was used in OpenZFS as DMU_BACKUP_FEATURE_RESUMING.  The
DMU_BACKUP_FEATURE_LARGE_DNODE flag must be shifted to 21 and
then reserved in the upstream OpenZFS implementation.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ned Bass <bass6@llnl.gov>
Closes #4795
2016-06-24 15:14:27 -07:00
Ned Bass 50c957f702 Implement large_dnode pool feature
Justification
-------------

This feature adds support for variable length dnodes. Our motivation is
to eliminate the overhead associated with using spill blocks.  Spill
blocks are used to store system attribute data (i.e. file metadata) that
does not fit in the dnode's bonus buffer. By allowing a larger bonus
buffer area the use of a spill block can be avoided.  Spill blocks
potentially incur an additional read I/O for every dnode in a dnode
block. As a worst case example, reading 32 dnodes from a 16k dnode block
and all of the spill blocks could issue 33 separate reads. Now suppose
those dnodes have size 1024 and therefore don't need spill blocks.  Then
the worst case number of blocks read is reduced to from 33 to two--one
per dnode block. In practice spill blocks may tend to be co-located on
disk with the dnode blocks so the reduction in I/O would not be this
drastic. In a badly fragmented pool, however, the improvement could be
significant.

ZFS-on-Linux systems that make heavy use of extended attributes would
benefit from this feature. In particular, ZFS-on-Linux supports the
xattr=sa dataset property which allows file extended attribute data
to be stored in the dnode bonus buffer as an alternative to the
traditional directory-based format. Workloads such as SELinux and the
Lustre distributed filesystem often store enough xattr data to force
spill bocks when xattr=sa is in effect. Large dnodes may therefore
provide a performance benefit to such systems.

Other use cases that may benefit from this feature include files with
large ACLs and symbolic links with long target names. Furthermore,
this feature may be desirable on other platforms in case future
applications or features are developed that could make use of a
larger bonus buffer area.

Implementation
--------------

The size of a dnode may be a multiple of 512 bytes up to the size of
a dnode block (currently 16384 bytes). A dn_extra_slots field was
added to the current on-disk dnode_phys_t structure to describe the
size of the physical dnode on disk. The 8 bits for this field were
taken from the zero filled dn_pad2 field. The field represents how
many "extra" dnode_phys_t slots a dnode consumes in its dnode block.
This convention results in a value of 0 for 512 byte dnodes which
preserves on-disk format compatibility with older software.

Similarly, the in-memory dnode_t structure has a new dn_num_slots field
to represent the total number of dnode_phys_t slots consumed on disk.
Thus dn->dn_num_slots is 1 greater than the corresponding
dnp->dn_extra_slots. This difference in convention was adopted
because, unlike on-disk structures, backward compatibility is not a
concern for in-memory objects, so we used a more natural way to
represent size for a dnode_t.

The default size for newly created dnodes is determined by the value of
a new "dnodesize" dataset property. By default the property is set to
"legacy" which is compatible with older software. Setting the property
to "auto" will allow the filesystem to choose the most suitable dnode
size. Currently this just sets the default dnode size to 1k, but future
code improvements could dynamically choose a size based on observed
workload patterns. Dnodes of varying sizes can coexist within the same
dataset and even within the same dnode block. For example, to enable
automatically-sized dnodes, run

 # zfs set dnodesize=auto tank/fish

The user can also specify literal values for the dnodesize property.
These are currently limited to powers of two from 1k to 16k. The
power-of-2 limitation is only for simplicity of the user interface.
Internally the implementation can handle any multiple of 512 up to 16k,
and consumers of the DMU API can specify any legal dnode value.

The size of a new dnode is determined at object allocation time and
stored as a new field in the znode in-memory structure. New DMU
interfaces are added to allow the consumer to specify the dnode size
that a newly allocated object should use. Existing interfaces are
unchanged to avoid having to update every call site and to preserve
compatibility with external consumers such as Lustre. The new
interfaces names are given below. The versions of these functions that
don't take a dnodesize parameter now just call the _dnsize() versions
with a dnodesize of 0, which means use the legacy dnode size.

New DMU interfaces:
  dmu_object_alloc_dnsize()
  dmu_object_claim_dnsize()
  dmu_object_reclaim_dnsize()

New ZAP interfaces:
  zap_create_dnsize()
  zap_create_norm_dnsize()
  zap_create_flags_dnsize()
  zap_create_claim_norm_dnsize()
  zap_create_link_dnsize()

The constant DN_MAX_BONUSLEN is renamed to DN_OLD_MAX_BONUSLEN. The
spa_maxdnodesize() function should be used to determine the maximum
bonus length for a pool.

These are a few noteworthy changes to key functions:

* The prototype for dnode_hold_impl() now takes a "slots" parameter.
  When the DNODE_MUST_BE_FREE flag is set, this parameter is used to
  ensure the hole at the specified object offset is large enough to
  hold the dnode being created. The slots parameter is also used
  to ensure a dnode does not span multiple dnode blocks. In both of
  these cases, if a failure occurs, ENOSPC is returned. Keep in mind,
  these failure cases are only possible when using DNODE_MUST_BE_FREE.

  If the DNODE_MUST_BE_ALLOCATED flag is set, "slots" must be 0.
  dnode_hold_impl() will check if the requested dnode is already
  consumed as an extra dnode slot by an large dnode, in which case
  it returns ENOENT.

* The function dmu_object_alloc() advances to the next dnode block
  if dnode_hold_impl() returns an error for a requested object.
  This is because the beginning of the next dnode block is the only
  location it can safely assume to either be a hole or a valid
  starting point for a dnode.

* dnode_next_offset_level() and other functions that iterate
  through dnode blocks may no longer use a simple array indexing
  scheme. These now use the current dnode's dn_num_slots field to
  advance to the next dnode in the block. This is to ensure we
  properly skip the current dnode's bonus area and don't interpret it
  as a valid dnode.

zdb
---
The zdb command was updated to display a dnode's size under the
"dnsize" column when the object is dumped.

For ZIL create log records, zdb will now display the slot count for
the object.

ztest
-----
Ztest chooses a random dnodesize for every newly created object. The
random distribution is more heavily weighted toward small dnodes to
better simulate real-world datasets.

Unused bonus buffer space is filled with non-zero values computed from
the object number, dataset id, offset, and generation number.  This
helps ensure that the dnode traversal code properly skips the interior
regions of large dnodes, and that these interior regions are not
overwritten by data belonging to other dnodes. A new test visits each
object in a dataset. It verifies that the actual dnode size matches what
was stored in the ztest block tag when it was created. It also verifies
that the unused bonus buffer space is filled with the expected data
patterns.

ZFS Test Suite
--------------
Added six new large dnode-specific tests, and integrated the dnodesize
property into existing tests for zfs allow and send/recv.

Send/Receive
------------
ZFS send streams for datasets containing large dnodes cannot be received
on pools that don't support the large_dnode feature. A send stream with
large dnodes sets a DMU_BACKUP_FEATURE_LARGE_DNODE flag which will be
unrecognized by an incompatible receiving pool so that the zfs receive
will fail gracefully.

While not implemented here, it may be possible to generate a
backward-compatible send stream from a dataset containing large
dnodes. The implementation may be tricky, however, because the send
object record for a large dnode would need to be resized to a 512
byte dnode, possibly kicking in a spill block in the process. This
means we would need to construct a new SA layout and possibly
register it in the SA layout object. The SA layout is normally just
sent as an ordinary object record. But if we are constructing new
layouts while generating the send stream we'd have to build the SA
layout object dynamically and send it at the end of the stream.

For sending and receiving between pools that do support large dnodes,
the drr_object send record type is extended with a new field to store
the dnode slot count. This field was repurposed from unused padding
in the structure.

ZIL Replay
----------
The dnode slot count is stored in the uppermost 8 bits of the lr_foid
field. The bits were unused as the object id is currently capped at
48 bits.

Resizing Dnodes
---------------
It should be possible to resize a dnode when it is dirtied if the
current dnodesize dataset property differs from the dnode's size, but
this functionality is not currently implemented. Clearly a dnode can
only grow if there are sufficient contiguous unused slots in the
dnode block, but it should always be possible to shrink a dnode.
Growing dnodes may be useful to reduce fragmentation in a pool with
many spill blocks in use. Shrinking dnodes may be useful to allow
sending a dataset to a pool that doesn't support the large_dnode
feature.

Feature Reference Counting
--------------------------
The reference count for the large_dnode pool feature tracks the
number of datasets that have ever contained a dnode of size larger
than 512 bytes. The first time a large dnode is created in a dataset
the dataset is converted to an extensible dataset. This is a one-way
operation and the only way to decrement the feature count is to
destroy the dataset, even if the dataset no longer contains any large
dnodes. The complexity of reference counting on a per-dnode basis was
too high, so we chose to track it on a per-dataset basis similarly to
the large_block feature.

Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3542
2016-06-24 13:13:21 -07:00
Ned Bass 68cbd56e18 Backfill metadnode more intelligently
Only attempt to backfill lower metadnode object numbers if at least
4096 objects have been freed since the last rescan, and at most once
per transaction group. This avoids a pathology in dmu_object_alloc()
that caused O(N^2) behavior for create-heavy workloads and
substantially improves object creation rates.  As summarized by
@mahrens in #4636:

"Normally, the object allocator simply checks to see if the next
object is available. The slow calls happened when dmu_object_alloc()
checks to see if it can backfill lower object numbers. This happens
every time we move on to a new L1 indirect block (i.e. every 32 *
128 = 4096 objects).  When re-checking lower object numbers, we use
the on-disk fill count (blkptr_t:blk_fill) to quickly skip over
indirect blocks that don’t have enough free dnodes (defined as an L2
with at least 393,216 of 524,288 dnodes free). Therefore, we may
find that a block of dnodes has a low (or zero) fill count, and yet
we can’t allocate any of its dnodes, because they've been allocated
in memory but not yet written to disk. In this case we have to hold
each of the dnodes and then notice that it has been allocated in
memory.

The end result is that allocating N objects in the same TXG can
require CPU usage proportional to N^2."

Add a tunable dmu_rescan_dnode_threshold to define the number of
objects that must be freed before a rescan is performed. Don't bother
to export this as a module option because testing doesn't show a
compelling reason to change it. The vast majority of the performance
gain comes from limit the rescan to at most once per TXG.

Signed-off-by: Ned Bass <bass6@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2016-06-24 13:13:12 -07:00
Paul Dagnelie bc77ba73fe OpenZFS 6513 - partially filled holes lose birth time
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Boris Protopopov <bprotopopov@hotmail.com>
Approved by: Richard Lowe <richlowe@richlowe.net>a
Ported by: Boris Protopopov <bprotopopov@actifio.com>
Signed-off-by: Boris Protopopov <bprotopopov@actifio.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>

OpenZFS-issue: https://www.illumos.org/issues/6513
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/8df0bcf0

If a ZFS object contains a hole at level one, and then a data block is
created at level 0 underneath that l1 block, l0 holes will be created.
However, these l0 holes do not have the birth time property set; as a
result, incremental sends will not send those holes.

Fix is to modify the dbuf_read code to fill in birth time data.
2016-06-21 10:55:13 -07:00
Gvozden Neskovic ab9f4b0b82 SIMD implementation of vdev_raidz generate and reconstruct routines
This is a new implementation of RAIDZ1/2/3 routines using x86_64
scalar, SSE, and AVX2 instruction sets. Included are 3 parity
generation routines (P, PQ, and PQR) and 7 reconstruction routines,
for all RAIDZ level. On module load, a quick benchmark of supported
routines will select the fastest for each operation and they will
be used at runtime. Original implementation is still present and
can be selected via module parameter.

Patch contains:
- specialized gen/rec routines for all RAIDZ levels,
- new scalar raidz implementation (unrolled),
- two x86_64 SIMD implementations (SSE and AVX2 instructions sets),
- fastest routines selected on module load (benchmark).
- cmd/raidz_test - verify and benchmark all implementations
- added raidz_test to the ZFS Test Suite

New zfs module parameters:
- zfs_vdev_raidz_impl (str): selects the implementation to use. On
  module load, the parameter will only accept first 3 options, and
  the other implementations can be set once module is finished
  loading. Possible values for this option are:
    "fastest" - use the fastest math available
    "original" - use the original raidz code
    "scalar" - new scalar impl
    "sse" - new SSE impl if available
    "avx2" - new AVX2 impl if available

See contents of `/sys/module/zfs/parameters/zfs_vdev_raidz_impl` to
get the list of supported values. If an implementation is not supported
on the system, it will not be shown. Currently selected option is
enclosed in `[]`.

Signed-off-by: Gvozden Neskovic <neskovic@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4328
2016-06-21 09:27:26 -07:00
Brian Behlendorf f74b821a66 Add `zfs allow` and `zfs unallow` support
ZFS allows for specific permissions to be delegated to normal users
with the `zfs allow` and `zfs unallow` commands.  In addition, non-
privileged users should be able to run all of the following commands:

  * zpool [list | iostat | status | get]
  * zfs [list | get]

Historically this functionality was not available on Linux.  In order
to add it the secpolicy_* functions needed to be implemented and mapped
to the equivalent Linux capability.  Only then could the permissions on
the `/dev/zfs` be relaxed and the internal ZFS permission checks used.

Even with this change some limitations remain.  Under Linux only the
root user is allowed to modify the namespace (unless it's a private
namespace).  This means the mount, mountpoint, canmount, unmount,
and remount delegations cannot be supported with the existing code.  It
may be possible to add this functionality in the future.

This functionality was validated with the cli_user and delegation test
cases from the ZFS Test Suite.  These tests exhaustively verify each
of the supported permissions which can be delegated and ensures only
an authorized user can perform it.

Two minor bug fixes were required for test-running.py.  First, the
Timer() object cannot be safely created in a `try:` block when there
is an unconditional `finally` block which references it.  Second,
when running as a normal user also check for scripts using the
both the .ksh and .sh suffixes.

Finally, existing users who are simulating delegations by setting
group permissions on the /dev/zfs device should revert that
customization when updating to a version with this change.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #362 
Closes #434 
Closes #4100
Closes #4394 
Closes #4410 
Closes #4487
2016-06-07 09:16:52 -07:00
Jinshan Xiong 1eeb4562a7 Implementation of AVX2 optimized Fletcher-4
New functionality:
- Preserves existing scalar implementation.
- Adds AVX2 optimized Fletcher-4 computation.
- Fastest routines selected on module load (benchmark).
- Test case for Fletcher-4 added to ztest.

New zcommon module parameters:
-  zfs_fletcher_4_impl (str): selects the implementation to use.
    "fastest" - use the fastest version available
    "cycle"   - cycle trough all available impl for ztest
    "scalar"  - use the original version
    "avx2"    - new AVX2 implementation if available

Performance comparison (Intel i7 CPU, 1MB data buffers):
- Scalar:  4216 MB/s
- AVX2:   14499 MB/s

See contents of `/sys/module/zcommon/parameters/zfs_fletcher_4_impl`
to get list of supported values. If an implementation is not supported
on the system, it will not be shown. Currently selected option is
enclosed in `[]`.

Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4330
2016-06-02 14:30:51 -07:00
Tony Hutter 26ef0cc7db OpenZFS 6531 - Provide mechanism to artificially limit disk performance
Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Approved by: Dan McDonald <danmcd@omniti.com>
Ported by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>

OpenZFS-issue: https://www.illumos.org/issues/6531
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/97e8130

Porting notes:
- Added new IO delay tracepoints, and moved common ZIO tracepoint macros
  to a new trace_common.h file.
- Used zio_delay_taskq() in place of OpenZFS's timeout_generic() function.
- Updated zinject man page
- Updated zpool_scrub test files
2016-05-26 10:11:51 -07:00
Tony Hutter 7e945072d1 Add request size histograms (-r) to zpool iostat, minor man page fix
Add -r option to "zpool iostat" to print request size histograms for the leaf
ZIOs. This includes histograms of individual ZIOs ("ind") and aggregate ZIOs
("agg"). These stats can be useful for seeing how well the ZFS IO aggregator
is working.

$ zpool iostat -r
mypool        sync_read    sync_write    async_read    async_write      scrub
req_size      ind    agg    ind    agg    ind    agg    ind    agg    ind    agg
----------  -----  -----  -----  -----  -----  -----  -----  -----  -----  -----
512             0      0      0      0      0      0    530      0      0      0
1K              0      0    260      0      0      0    116    246      0      0
2K              0      0      0      0      0      0      0    431      0      0
4K              0      0      0      0      0      0      3    107      0      0
8K             15      0     35      0      0      0      0      6      0      0
16K             0      0      0      0      0      0      0     39      0      0
32K             0      0      0      0      0      0      0      0      0      0
64K            20      0     40      0      0      0      0      0      0      0
128K            0      0     20      0      0      0      0      0      0      0
256K            0      0      0      0      0      0      0      0      0      0
512K            0      0      0      0      0      0      0      0      0      0
1M              0      0      0      0      0      0      0      0      0      0
2M              0      0      0      0      0      0      0      0      0      0
4M              0      0      0      0      0      0    155     19      0      0
8M              0      0      0      0      0      0      0    811      0      0
16M             0      0      0      0      0      0      0     68      0      0
--------------------------------------------------------------------------------

Also rename the stray "-G" in the man page to be "-w" for latency histograms.

Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Closes #4659
2016-05-25 15:49:35 -07:00
Chunwei Chen 9baaa7deae Linux 4.7 compat: use iterate_shared for concurrent readdir
Register iterate_shared if it exists so the kernel will used shared
lock and allowing concurrent readdir.

Also, use shared lock when doing llseek with SEEK_DATA or SEEK_HOLE
to allow concurrent seeking.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4664
Closes #4665
2016-05-20 11:09:16 -07:00
Nikolay Borisov 278f223668 Kill znode->z_gen field
This field is a duplicate of the inode->i_generation, so just
kill it.

Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
Signed-off-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4538
Closes #4654
2016-05-19 13:06:14 -07:00
Brian Behlendorf ada8258141 Revert "zhack: Add 'feature disable' command"
This reverts commit 8302528617 and
ebecfcd699 which broke the build.
While these patches do apply cleanly and passed previous test
runs they need to be updated to account for the changes made in
commit 241b541574.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #3878
2016-05-17 11:52:07 -07:00
Brian Behlendorf 8302528617 zhack: Add 'feature disable' command
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #3878
2016-05-17 11:00:21 -07:00
Boris Protopopov e3a07cd033 Use zfs range locks in ztest
The zfs range lock interface no longer tightly depends on a
znode_t and therefore can be used in ztest.  This allows the
previous ztest specific implementation to be removed, and for
additional test coverage of the shared version.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Boris Protopopov <boris.protopopov@actifio.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4023
Issue #4024
2016-05-17 10:40:30 -07:00
Chunwei Chen d88895a069 Remove dummy znode from zvol_state
struct zvol_state contains a dummy znode, which is around 1KB on x64,
only for zfs_range_lock. But in reality, other than z_range_lock and
z_range_avl, zfs_range_lock only need znode on regular file, which
means we add 1KB on a structure and gain nothing.

In this patch, we remove the dummy znode for zvol_state. In order to
do that, we also need to refactor zfs_range_lock a bit. We move
z_range_lock and z_range_avl pair out of znode_t to form zfs_rlock_t.
This new struct replaces znode_t as the main handle inside the range
lock functions.

We also add pointers to z_size, z_blksz, and z_max_blksz so range lock
code doesn't depend on znode_t.  This allows non-ZPL consumers like
Lustre to use the range locks with their equivalent znode_t structure.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Boris Protopopov <boris.protopopov@actifio.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4510
2016-05-17 10:29:02 -07:00
Denys Rtveliashvili 206971d234 OpenZFS 6739 - assumption in cv_timedwait_hires
Userland version of cv_timedwait_hires() always assumes absolute time.

Reviewed by: Paul Dagnelie <pcd@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>
Approved by: Robert Mustacchi <rm@joyent.com>
Ported by: Denys Rtveliashvili <denys@rtveliashvili.name>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>

OpenZFS-issue: https://www.illumos.org/issues/6739
OpenZFS-commit: https://github.com/illumos/illumos-gate/commit/41c6413

Porting Notes:
The ported change has revealed a number of problems in the Linux-specific code,
as it was expecting incorrect return codes from pthread_* functions.
Reviewed and improved the usage of pthread_* function in lib/libzpool/kernel.c.
2016-05-15 15:18:25 -07:00
Chunwei Chen a9bb2b6827 Use cv_timedwait_sig_hires in arc_reclaim_thread
The was originally using interruptible cv_timedwait_sig, but was changed
to uninterruptible cv_timedwait_hires in ae6d0c6. Use _sig_hires instead
to allow interruptible sleep.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4633
Closes #4634
2016-05-12 14:56:47 -07:00
Brian Behlendorf c15706490e Revert "Kill znode->z_gen field"
This reverts commit 4cd77889b6.  The
i_generation field in the inode is 32-bit and the SA code expects
64-bit fixed values.  Revert this optimization for now until
this is cleanly addressed.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4538
2016-05-12 13:36:22 -07:00
Tony Hutter 193a37cb24 Add -lhHpw options to "zpool iostat" for avg latency, histograms, & queues
Update the zfs module to collect statistics on average latencies, queue sizes,
and keep an internal histogram of all IO latencies.  Along with this, update
"zpool iostat" with some new options to print out the stats:

-l: Include average IO latencies stats:

 total_wait     disk_wait    syncq_wait    asyncq_wait  scrub
 read  write   read  write   read  write   read  write   wait
-----  -----  -----  -----  -----  -----  -----  -----  -----
    -   41ms      -    2ms      -   46ms      -    4ms      -
    -    5ms      -    1ms      -    1us      -    4ms      -
    -    5ms      -    1ms      -    1us      -    4ms      -
    -      -      -      -      -      -      -      -      -
    -   49ms      -    2ms      -   47ms      -      -      -
    -      -      -      -      -      -      -      -      -
    -    2ms      -    1ms      -      -      -    1ms      -
-----  -----  -----  -----  -----  -----  -----  -----  -----
  1ms    1ms    1ms  413us   16us   25us      -    5ms      -
  1ms    1ms    1ms  413us   16us   25us      -    5ms      -
  2ms    1ms    2ms  412us   26us   25us      -    5ms      -
    -    1ms      -  413us      -   25us      -    5ms      -
    -    1ms      -  460us      -   29us      -    5ms      -
196us    1ms  196us  370us    7us   23us      -    5ms      -
-----  -----  -----  -----  -----  -----  -----  -----  -----

-w: Print out latency histograms:

sdb           total           disk         sync_queue      async_queue
latency    read   write    read   write    read   write    read   write   scrub
-------  ------  ------  ------  ------  ------  ------  ------  ------  ------
1ns           0       0       0       0       0       0       0       0       0
...
33us          0       0       0       0       0       0       0       0       0
66us          0       0     107    2486       2     788      12      12       0
131us         2     797     359    4499      10     558     184     184       6
262us        22     801     264    1563      10     286     287     287      24
524us        87     575      71   52086      15    1063     136     136      92
1ms         152    1190       5   41292       4    1693     252     252     141
2ms         245    2018       0   50007       0    2322     371     371     220
4ms         189    7455      22  162957       0    3912    6726    6726     199
8ms         108    9461       0  102320       0    5775    2526    2526      86
17ms         23   11287       0   37142       0    8043    1813    1813      19
34ms          0   14725       0   24015       0   11732    3071    3071       0
67ms          0   23597       0    7914       0   18113    5025    5025       0
134ms         0   33798       0     254       0   25755    7326    7326       0
268ms         0   51780       0      12       0   41593   10002   10002       0
537ms         0   77808       0       0       0   64255   13120   13120       0
1s            0  105281       0       0       0   83805   20841   20841       0
2s            0   88248       0       0       0   73772   14006   14006       0
4s            0   47266       0       0       0   29783   17176   17176       0
9s            0   10460       0       0       0    4130    6295    6295       0
17s           0       0       0       0       0       0       0       0       0
34s           0       0       0       0       0       0       0       0       0
69s           0       0       0       0       0       0       0       0       0
137s          0       0       0       0       0       0       0       0       0
-------------------------------------------------------------------------------

-h: Help

-H: Scripted mode. Do not display headers, and separate fields by a single
    tab instead of arbitrary space.

-q: Include current number of entries in sync & async read/write queues,
    and scrub queue:

 syncq_read    syncq_write   asyncq_read  asyncq_write   scrubq_read
 pend  activ   pend  activ   pend  activ   pend  activ   pend  activ
-----  -----  -----  -----  -----  -----  -----  -----  -----  -----
    0      0      0      0     78     29      0      0      0      0
    0      0      0      0     78     29      0      0      0      0
    0      0      0      0      0      0      0      0      0      0
    -      -      -      -      -      -      -      -      -      -
    0      0      0      0      0      0      0      0      0      0
    -      -      -      -      -      -      -      -      -      -
    0      0      0      0      0      0      0      0      0      0
-----  -----  -----  -----  -----  -----  -----  -----  -----  -----
    0      0    227    394      0     19      0      0      0      0
    0      0    227    394      0     19      0      0      0      0
    0      0    108     98      0     19      0      0      0      0
    0      0     19     98      0      0      0      0      0      0
    0      0     78     98      0      0      0      0      0      0
    0      0     19     88      0      0      0      0      0      0
-----  -----  -----  -----  -----  -----  -----  -----  -----  -----

-p: Display numbers in parseable (exact) values.

Also, update iostat syntax to allow the user to specify specific vdevs
to show statistics for.  The three options for choosing pools/vdevs are:

Display a list of pools:
    zpool iostat ... [pool ...]

Display a list of vdevs from a specific pool:
    zpool iostat ... [pool vdev ...]

Display a list of vdevs from any pools:
    zpool iostat ... [vdev ...]

Lastly, allow zpool command "interval" value to be floating point:
    zpool iostat -v 0.5

Signed-off-by: Tony Hutter <hutter2@llnl.gov
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4433
2016-05-12 12:36:32 -07:00
Joe Stein e0ab3ab553 OpenZFS 6736 - ZFS per-vdev ZAPs
6736 ZFS per-vdev ZAPs
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Don Brady <don.brady@intel.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>

References:
  https://www.illumos.org/issues/6736
  https://github.com/openzfs/openzfs/commit/215198a

Ported-by: Don Brady <don.brady@intel.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4515
2016-05-02 14:27:45 -07:00
Nikolay Borisov 4cd77889b6 Kill znode->z_gen field
This field is a duplicate of the inode->i_generation, so just kill it

Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4538
2016-05-02 11:22:31 -07:00
Alex Reece 463a8cfe2b Illumos 6844 - dnode_next_offset can detect fictional holes
6844 dnode_next_offset can detect fictional holes
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>

dnode_next_offset is used in a variety of places to iterate over the
holes or allocated blocks in a dnode. It operates under the premise that
it can iterate over the blockpointers of a dnode in open context while
holding only the dn_struct_rwlock as reader. Unfortunately, this premise
does not hold.

When we create the zio for a dbuf, we pass in the actual block pointer
in the indirect block above that dbuf. When we later zero the bp in
zio_write_compress, we are directly modifying the bp. The state of the
bp is now inconsistent from the perspective of dnode_next_offset: the bp
will appear to be a hole until zio_dva_allocate finally finishes filling
it in. In the meantime, dnode_next_offset can detect a hole in the dnode
when none exists.

I was able to experimentally demonstrate this behavior with the
following setup:
1. Create a file with 1 million dbufs.
2. Create a thread that randomly dirties L2 blocks by writing to the
first L0 block under them.
3. Observe dnode_next_offset, waiting for it to skip over a hole in the
middle of a file.
4. Do dnode_next_offset in a loop until we skip over such a non-existent
hole.

The fix is to ensure that it is valid to iterate over the indirect
blocks in a dnode while holding the dn_struct_rwlock by passing the zio
a copy of the BP and updating the actual BP in dbuf_write_ready while
holding the lock.

References:
  https://www.illumos.org/issues/6844
  https://github.com/openzfs/openzfs/pull/82
  DLPX-35372

Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4548
2016-04-27 16:24:15 -07:00
Brian Behlendorf da5e151f20 Add pn_alloc()/pn_free() functions
In order to remove the HAVE_PN_UTILS wrappers the pn_alloc() and
pn_free() functions must be implemented.  The existing illumos
implementation were used for this purpose.

The `flags` argument which was used in places wrapped by the
HAVE_PN_UTILS condition has beed added back to zfs_remove() and
zfs_link() functions.  This removes a small point of divergence
between the ZoL code and upstream.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4522
2016-04-21 09:49:25 -07:00
Chunwei Chen 6760077194 Make zfs mount according to relatime config in dataset
Also enable lazytime in mount.zfs

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4482
2016-04-05 18:55:59 -07:00
Chunwei Chen 0df9673f01 Fix atime handling and relatime
The problem for atime:

We have 3 places for atime: inode->i_atime, znode->z_atime and SA. And its
handling is a mess. A huge part of mess regarding atime comes from
zfs_tstamp_update_setup, zfs_inode_update, and zfs_getattr, which behave
inconsistently with those three values.

zfs_tstamp_update_setup clears z_atime_dirty unconditionally as long as you
don't pass ATTR_ATIME. Which means every write(2) operation which only updates
ctime and mtime will cause atime changes to not be written to disk.

Also zfs_inode_update from write(2) will replace inode->i_atime with what's
inside SA(stale). But doesn't touch z_atime. So after read(2) and write(2).
You'll have i_atime(stale), z_atime(new), SA(stale) and z_atime_dirty=0.

Now, if you do stat(2), zfs_getattr will actually replace i_atime with what's
inside, z_atime. So you will have now you'll have i_atime(new), z_atime(new),
SA(stale) and z_atime_dirty=0. These will all gone after umount. And you'll
leave with a stale atime.

The problem for relatime:

We do have a relatime config inside ZFS dataset, but how it should interact
with the mount flag MS_RELATIME is not well defined. It seems it wanted
relatime mount option to override the dataset config by showing it as
temporary in `zfs get`. But at the same time, `zfs set relatime=on|off` would
also seems to want to override the mount option. Not to mention that
MS_RELATIME flag is actually never passed into ZFS, so it never really worked.

How Linux handles atime:

The Linux kernel actually handles atime completely in VFS, except for writing
it to disk. So if we remove the atime handling in ZFS, things would just work,
no matter it's strictatime, relatime, noatime, or even O_NOATIME. And whenever
VFS updates the i_atime, it will notify the underlying filesystem via
sb->dirty_inode().

And also there's one thing to note about atime flags like MS_RELATIME and
other flags like MS_NODEV, etc. They are mount point flags rather than
filesystem(sb) flags. Since native linux filesystem can be mounted at multiple
places at the same time, they can all have different atime settings. So these
flags are never passed down to filesystem drivers.

What this patch tries to do:

We remove znode->z_atime, since we won't gain anything from it. We remove most
of the atime handling and leave it to VFS. The only thing we do with atime is
to write it when dirty_inode() or setattr() is called. We also add
file_accessed() in zpl_read() since it's not provided in vfs_read().

After this patch, only the MS_RELATIME flag will have effect. The setting in
dataset won't do anything. We will make zfstuil to mount ZFS with MS_RELATIME
set according to the setting in dataset in future patch.

Signed-off-by: Chunwei Chen <david.chen@osnexus.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4482
2016-04-05 18:54:55 -07:00
Carlo Landmeter 1a01c207cb Ensure correct return value type
When compiling with musl libc the return type will be incorrect.

Signed-off-by: Carlo Landmeter <clandmeter@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4454
2016-03-29 18:33:17 -07:00
Boris Protopopov a0bd735adb Add support for asynchronous zvol minor operations
zfsonlinux issue #2217 - zvol minor operations: check snapdev
property before traversing snapshots of a dataset

zfsonlinux issue #3681 - lock order inversion between zvol_open()
and dsl_pool_sync()...zvol_rename_minors()

Create a per-pool zvol taskq for asynchronous zvol tasks.
There are a few key design decisions to be aware of.

* Each taskq must be single threaded to ensure tasks are always
  processed in the order in which they were dispatched.

* There is a taskq per-pool in order to keep the pools independent.
  This way if one pool is suspended it will not impact another.

* The preferred location to dispatch a zvol minor task is a sync
  task.  In this context there is easy access to the spa_t and
  minimal error handling is required because the sync task must
  succeed.

Support for asynchronous zvol minor operations address issue #3681.

Signed-off-by: Boris Protopopov <boris.protopopov@actifio.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2217
Closes #3678
Closes #3681
2016-03-10 09:49:22 -08:00
smh 9f500936c8 FreeBSD r256956: Improve ZFS N-way mirror read performance by using load and locality information.
The existing algorithm selects a preferred leaf vdev based on offset of the zio
request modulo the number of members in the mirror. It assumes the devices are
of equal performance and that spreading the requests randomly over both drives
will be sufficient to saturate them. In practice this results in the leaf vdevs
being under utilized.

The new algorithm takes into the following additional factors:
* Load of the vdevs (number outstanding I/O requests)
* The locality of last queued I/O vs the new I/O request.

Within the locality calculation additional knowledge about the underlying vdev
is considered such as; is the device backing the vdev a rotating media device.

This results in performance increases across the board as well as significant
increases for predominantly streaming loads and for configurations which don't
have evenly performing devices.

The following are results from a setup with 3 Way Mirror with 2 x HD's and
1 x SSD from a basic test running multiple parrallel dd's.

With pre-fetch disabled (vfs.zfs.prefetch_disable=1):

== Stripe Balanced (default) ==
Read 15360MB using bs: 1048576, readers: 3, took 161 seconds @ 95 MB/s
== Load Balanced (zfslinux) ==
Read 15360MB using bs: 1048576, readers: 3, took 297 seconds @ 51 MB/s
== Load Balanced (locality freebsd) ==
Read 15360MB using bs: 1048576, readers: 3, took 54 seconds @ 284 MB/s

With pre-fetch enabled (vfs.zfs.prefetch_disable=0):

== Stripe Balanced (default) ==
Read 15360MB using bs: 1048576, readers: 3, took 91 seconds @ 168 MB/s
== Load Balanced (zfslinux) ==
Read 15360MB using bs: 1048576, readers: 3, took 108 seconds @ 142 MB/s
== Load Balanced (locality freebsd) ==
Read 15360MB using bs: 1048576, readers: 3, took 48 seconds @ 320 MB/s

In addition to the performance changes the code was also restructured, with
the help of Justin Gibbs, to provide a more logical flow which also ensures
vdevs loads are only calculated from the set of valid candidates.

The following additional sysctls where added to allow the administrator
to tune the behaviour of the load algorithm:
* vfs.zfs.vdev.mirror.rotating_inc
* vfs.zfs.vdev.mirror.rotating_seek_inc
* vfs.zfs.vdev.mirror.rotating_seek_offset
* vfs.zfs.vdev.mirror.non_rotating_inc
* vfs.zfs.vdev.mirror.non_rotating_seek_inc

These changes where based on work started by the zfsonlinux developers:
https://github.com/zfsonlinux/zfs/pull/1487

Reviewed by:	gibbs, mav, will
MFC after:	2 weeks
Sponsored by:	Multiplay

References:
  https://github.com/freebsd/freebsd@5c7a6f5d
  https://github.com/freebsd/freebsd@31b7f68d
  https://github.com/freebsd/freebsd@e186f564

Performance Testing:
  https://github.com/zfsonlinux/zfs/pull/4334#issuecomment-189057141

Porting notes:
- The tunables were adjusted to have ZoL-style names.
- The code was modified to use ZoL's vd_nonrot.
- Fixes were done to make cstyle.pl happy
- Merge conflicts were handled manually
- freebsd/freebsd@e186f564bc by my
  collegue Andriy Gapon has been included. It applied perfectly, but
  added a cstyle regression.
- This replaces 556011dbec entirely.
- A typo "IO'a" has been corrected to say "IO's"
- Descriptions of new tunables were added to man/man5/zfs-module-parameters.5.

Ported-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4334
2016-02-26 11:24:35 -08:00
Brian Behlendorf b6fcb792ca Illumos 6414 - vdev_config_sync could be simpler
6414 vdev_config_sync could be simpler
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Approved by: Robert Mustacchi <rm@joyent.com>

References:
  https://www.illumos.org/issues/6414
  https://github.com/illumos/illumos-gate/commit/eb5bb58

Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Chunwei Chen <tuxoko@gmail.com>
2016-01-28 12:44:39 -05:00
Brian Behlendorf 519129ff4e Illumos 6815179, 6844191
6815179 zpool import with a large number of LUNs is too slow
6844191 zpool import, scanning of disks should be multi-threaded

References:
  https://github.com/illumos/illumos-gate/commit/4f67d75

Porting notes:
- This change was originally never ported to Linux due to it
  dependence on the thread pool interface.  This patch solves
  that issue by switching the code to use the existing taskq
  implementation which provides the same basic functionality.
  However, in order for this to work properly thread_init()
  and thread_fini() must be called around to taskq consumer
  to perform the needed thread initialization.

- The check_one_slice, nozpool_all_slices, and check_slices
  functions have been disabled for Linux.  They are difficult,
  but possible, to implement for Linux due to how partitions
  are get names.  Since this is only an optimization this code
  can be added at a latter date.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2016-01-22 09:39:46 -08:00
Matthew Ahrens 19d55079ae Illumos 4950 - files sometimes can't be removed from a full filesystem
4950 files sometimes can't be removed from a full filesystem
Reviewed by: Adam Leventhal <adam.leventhal@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Sebastien Roy <sebastien.roy@delphix.com>
Reviewed by: Boris Protopopov <bprotopopov@hotmail.com>
Approved by: Dan McDonald <danmcd@omniti.com>

References:
  https://www.illumos.org/issues/4950
  https://github.com/illumos/illumos-gate/commit/4bb7380

Porting notes:
- ZoL currently does not log discards to zvols, so the portion of
  this patch that modifies the discard logging to mark it as
  freeing space has been discarded.

2. may_delete_now had been removed from zfs_remove() in ZoL.
   It has been reintroduced.

3. We do not try to emulate vnodes, so the following lines are
   not valid on Linux:

	mutex_enter(&vp->v_lock);
	may_delete_now = vp->v_count == 1 && !vn_has_cached_data(vp);
	mutex_exit(&vp->v_lock);

  This has been replaced with:

	mutex_enter(&zp->z_lock);
	may_delete_now = atomic_read(&ip->i_count) == 1 && !(zp->z_is_mapped);
	mutex_exit(&zp->z_lock);

Ported-by: Richard Yao <richard.yao@clusterhq.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2016-01-21 16:59:30 -08:00
Josef 'Jeff' Sipek bc89ac8479 Illumos 5045 - use atomic_{inc,dec}_* instead of atomic_add_*
5045 use atomic_{inc,dec}_* instead of atomic_add_*
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Garrett D'Amore <garrett@damore.org>
Approved by: Robert Mustacchi <rm@joyent.com>

References:
  https://www.illumos.org/issues/5045
  https://github.com/illumos/illumos-gate/commit/1a5e258

Porting notes:
- All changes to non-ZFS files dropped.
- Changes to zfs_vfsops.c dropped because they were Illumos specific.

Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4220
2016-01-15 15:38:36 -08:00
Richard Yao 546f38433a SET_ERROR should print strings
When debugging with tracepoints, we see string pointers:

zfs  3017 [006]  8878.728915: zfs:zfs_set__error: ffffffffa0eec3fc:3013:ffffffffa0ebcd60(): error 0x2
        ffffffffa0e1ca43 spa_open_common (/lib/modules/3.12.21-gentoo-r1/extra/zfs/zfs.ko)
        ffffffffa0e1cbe3 spa_open (/lib/modules/3.12.21-gentoo-r1/extra/zfs/zfs.ko)
        ffffffffa0e6f6ef zfs_ioc_stable (/lib/modules/3.12.21-gentoo-r1/extra/zfs/zfs.ko)
        ffffffffa0e6f2a9 zfsdev_ioctl (/lib/modules/3.12.21-gentoo-r1/extra/zfs/zfs.ko)
        ffffffff811909dd do_vfs_ioctl ([kernel.kallsyms])
        ffffffff81190c41 sys_ioctl ([kernel.kallsyms])
        ffffffff8156e2e9 system_call_fastpath ([kernel.kallsyms])
            7ff7d8be69c7 __GI___ioctl (/lib64/libc-2.19.so)
            7ff7d90cac53 lzc_ioctl.constprop.3 (/lib64/libzfs_core.so.1.0.0)
        636f695f637a6c00 [unknown] ([unknown])

Printing the actual strings is more convenient:

zfs  3461 [001] 10599.847692: zfs:zfs_set__error: spa.c:3013:spa_open_common(): error 0x2
        ffffffffa116ba43 spa_open_common (/lib/modules/3.12.21-gentoo-r1/extra/zfs/zfs.ko)
        ffffffffa116bbe3 spa_open (/lib/modules/3.12.21-gentoo-r1/extra/zfs/zfs.ko)
        ffffffffa11be8df zfs_ioc_stable (/lib/modules/3.12.21-gentoo-r1/extra/zfs/zfs.ko)
        ffffffffa11be499 zfsdev_ioctl (/lib/modules/3.12.21-gentoo-r1/extra/zfs/zfs.ko)
        ffffffff811909dd do_vfs_ioctl ([kernel.kallsyms])
        ffffffff81190c41 sys_ioctl ([kernel.kallsyms])
        ffffffff8156e2e9 system_call_fastpath ([kernel.kallsyms])
            7f11b843c9c7 __GI___ioctl (/lib64/libc-2.19.so)
            7f11b8920c53 lzc_ioctl.constprop.3 (/lib64/libzfs_core.so.1.0.0)
        636f695f637a6c00 [unknown] ([unknown])

A few other tracepoints have strings as well, so switch to printing
the actual string values at the same time.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4212
2016-01-15 15:38:35 -08:00
Richard Yao b10695c8f1 Remove fastwrite mutex
The fast write mutex is intended to protect accounting, but it is
redundant because all accounting is performed through atomic operations.
It also serializes all metaslab IO behind a mutex, which introduces a
theoretical scaling regression that the Illumos developers did not like
when we showed this to them. Removing it makes the selection of the
metaslab_group lock free as it is on Illumos. The selection is not quite
the same without the lock because the loop races with IO completions,
but any imbalances caused by this are likely to be corrected by
subsequent metaslab group selections.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #3643
2016-01-15 15:38:35 -08:00
Brian Behlendorf c96c36fa22 Fix zsb->z_hold_mtx deadlock
The zfs_znode_hold_enter() / zfs_znode_hold_exit() functions are used to
serialize access to a znode and its SA buffer while the object is being
created or destroyed.  This kind of locking would normally reside in the
znode itself but in this case that's impossible because the znode and SA
buffer may not yet exist.  Therefore the locking is handled externally
with an array of mutexs and AVLs trees which contain per-object locks.

In zfs_znode_hold_enter() a per-object lock is created as needed, inserted
in to the correct AVL tree and finally the per-object lock is held.  In
zfs_znode_hold_exit() the process is reversed.  The per-object lock is
released, removed from the AVL tree and destroyed if there are no waiters.

This scheme has two important properties:

1) No memory allocations are performed while holding one of the z_hold_locks.
   This ensures evict(), which can be called from direct memory reclaim, will
   never block waiting on a z_hold_locks which just happens to have hashed
   to the same index.

2) All locks used to serialize access to an object are per-object and never
   shared.  This minimizes lock contention without creating a large number
   of dedicated locks.

On the downside it does require znode_lock_t structures to be frequently
allocated and freed.  However, because these are backed by a kmem cache
and very short lived this cost is minimal.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #4106
2016-01-15 15:33:45 -08:00
Brian Behlendorf 0720116d4d Add zfs_object_mutex_size module option
Add a zfs_object_mutex_size module option to facilitate resizing the
the per-dataset znode mutex array.  Increasing this value may help
make the deadlock described in #4106 less common, but this is not a
proper fix.  This patch is primarily to aid debugging and analysis.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tim Chase <tim@chase2k.com>
Issue #4106
2016-01-15 15:33:44 -08:00