ed2f7ba08d
Previously the primarycache property was handled only in the dbuf layer. Since the speculative prefetcher is implemented in the ARC, it had to be disabled for uncacheable buffers. This change gives the ARC knowledge about uncacheable buffers via arc_read() and arc_write(). So when remove_reference() drops the last reference on the ARC header, it can either immediately destroy it, or if it is marked as prefetch, put it into a new arc_uncached state. That state is scanned every second, evicting stale buffers that were not demand read. This change also tracks dbufs that were read from the beginning, but not to the end. It is assumed that such buffers may receive further reads, and so they are stored in dbuf cache. If a following reads reaches the end of the buffer, it is immediately evicted. Otherwise it will follow regular dbuf cache eviction. Since the dbuf layer does not know actual file sizes, this logic is not applied to the final buffer of a dnode. Since uncacheable buffers should no longer stay in the ARC for long, this patch also tries to optimize I/O by allocating ARC physical buffers as linear to allow buffer sharing. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: George Wilson <george.wilson@delphix.com> Reviewed-by: Ryan Moeller <ryan@iXsystems.com> Signed-off-by: Alexander Motin <mav@FreeBSD.org> Sponsored by: iXsystems, Inc. Closes #14243 |
||
|---|---|---|
| .github | ||
| cmd | ||
| config | ||
| contrib | ||
| etc | ||
| include | ||
| lib | ||
| man | ||
| module | ||
| rpm | ||
| scripts | ||
| tests | ||
| udev | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmodules | ||
| AUTHORS | ||
| CODE_OF_CONDUCT.md | ||
| COPYRIGHT | ||
| LICENSE | ||
| META | ||
| Makefile.am | ||
| NEWS | ||
| NOTICE | ||
| README.md | ||
| RELEASES.md | ||
| TEST | ||
| autogen.sh | ||
| configure.ac | ||
| copy-builtin | ||
| zfs.release.in | ||
README.md
OpenZFS is an advanced file system and volume manager which was originally developed for Solaris and is now maintained by the OpenZFS community. This repository contains the code for running OpenZFS on Linux and FreeBSD.
Official Resources
- Documentation - for using and developing this repo
- ZoL Site - Linux release info & links
- Mailing lists
- OpenZFS site - for conference videos and info on other platforms (illumos, OSX, Windows, etc)
Installation
Full documentation for installing OpenZFS on your favorite operating system can be found at the Getting Started Page.
Contribute & Develop
We have a separate document with contribution guidelines.
We have a Code of Conduct.
Release
OpenZFS is released under a CDDL license.
For more details see the NOTICE, LICENSE and COPYRIGHT files; UCRL-CODE-235197
Supported Kernels
- The
METAfile contains the officially recognized supported Linux kernel versions. - Supported FreeBSD versions are any supported branches and releases starting from 12.2-RELEASE.