Alexander Motin
0d1f3b1c60
Profiling RAIDZ1/dRAID1 resilver I've noticed that they calculate the parity twice for most of blocks: first to reconstruct the data column and then to "verify" the parity column. Same time it is obvious that parity generated from data reconstructed from the parity will be identical to the original. The code even had this condition, but it was overridden by ZIO_FLAG_RESILVER check. I think the ZIO_FLAG_RESILVER condition is not right. Instead we should check for parity_errors > 0, when we failed to read some parity columns that we'll need to rewrite. It should not matter if we are resilvering or just doing self healing on regular read. Profiling shows this saving ~16% of ZFS CPU time when resilvering RAIDZ1. RAIDZ2+ are out of luck, unless two disks are replaced same time, since there is still a parity to verify. Reviewed-by: Brian Behlendorf <[email protected]> Signed-off-by: Alexander Motin <[email protected]> Closes #18707
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 and Distributions
Linux
Given the wide variety of Linux environments, we prioritize development and testing on stable, supported kernels and distributions.
Kernel (kernel.org)
All longterm kernels from kernel.org are supported. stable kernels are usually supported in the next OpenZFS release.
Supported longterm kernels: 6.18, 6.12, 6.6, 6.1, 5.15, 5.10.
Red Hat Enterprise Linux (RHEL)
All RHEL (and compatible systems: AlmaLinux OS, Rocky Linux, etc) on the full or maintenance support tracks are supported.
Supported RHEL releases: 8.10, 9.7, 10.1.
Ubuntu
All Ubuntu LTS releases are supported.
Supported Ubuntu releases: 26.04 “Resolute”, 24.04 “Noble”, 22.04 “Jammy”.
Debian
All Debian stable and LTS releases are supported.
Supported Debian releases: 13 “Trixie”, 12 “Bookworm”, 11 “Bullseye”.
Other Distributions
Generally, if a distribution is following an LTS kernel, it should work well with OpenZFS.
FreeBSD
All FreeBSD releases receiving security support are supported by OpenZFS.
Supported FreeBSD releases: 15.1, 14.4.