zed monitors ZFS events. When a zevent is posted, zed will run any
scripts that have been enabled for the corresponding zevent class.
Multiple scripts may be invoked for a given zevent. The zevent
nvpairs are passed to the scripts as environment variables.
Events are processed synchronously by the single thread, and there is
no maximum timeout for script execution. Consequently, a misbehaving
script can delay (or forever block) the processing of subsequent
zevents. Plans are to address this in future commits.
Initial scripts have been developed to log events to syslog
and send email in response to checksum/data/io errors and
resilver.finish/scrub.finish events. By default, email will only
be sent if the ZED_EMAIL variable is configured in zed.rc (which is
serving as a config file of sorts until a proper configuration file
is implemented).
Signed-off-by: Chris Dunlap <cdunlap@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #2
When your kernel is built with kernel stack tracing enabled and you
have the debugfs filesystem mounted. Then the zfs.sh script will clear
the worst observed kernel stack depth on module load and check the worst
case usage on module removal. If the stack depth ever exceeds 7000
bytes the full stack will be printed for debugging. This is dangerously
close to overrunning the default 8k stack.
This additional advisory debugging is particularly valuable when running
the regression tests on a kernel built with 16k stacks. In this case,
almost no matter how bad the stack overrun is you will see be able to
get a clean stack trace for debugging. Since the worst case stack usage
can be highly variable it's helpful to always check the worst case usage.
Before it is safe to unload the zfs module stack all mounted
zfs filesystems must be unmounted. If they are not unmounted,
there will be references held on the modules and the stack cannot
be removed. To handle this have 'zfs.sh -u' which is used by all
of the test scripts umount all zfs filesystem before attempting
to unload the module stack.
Occasional failures were observed in zconfig.sh because udev
could be delayed for a few seconds. To handle this the wait_udev
function has been added to wait for timeout seconds for an
expected device before returning an error. By default callers
currently use a 30 seconds timeout which should be much longer
than udev ever needs but not so long to worry the test suite
is hung.
Add autoconf style build infrastructure to the ZFS tree. This
includes autogen.sh, configure.ac, m4 macros, some scripts/*,
and makefiles for all the core ZFS components.
Chris Dunlap
Brian Behlendorf