Go to file
Alexander Motin 734eba251d
Wire O_DIRECT also to Uncached I/O (#17218)
Before Direct I/O was implemented, I've implemented lighter version
I called Uncached I/O.  It uses normal DMU/ARC data path with some
optimizations, but evicts data from caches as soon as possible and
reasonable.  Originally I wired it only to a primarycache property,
but now completing the integration all the way up to the VFS.

While Direct I/O has the lowest possible memory bandwidth usage,
it also has a significant number of limitations.  It require I/Os
to be page aligned, does not allow speculative prefetch, etc.  The
Uncached I/O does not have those limitations, but instead require
additional memory copy, though still one less than regular cached
I/O.  As such it should fill the gap in between.  Considering this
I've disabled annoying EINVAL errors on misaligned requests, adding
a tunable for those who wants to test their applications.

To pass the information between the layers I had to change a number
of APIs.  But as side effect upper layers can now control not only
the caching, but also speculative prefetch.  I haven't wired it to
VFS yet, since it require looking on some OS specifics.  But while
there I've implemented speculative prefetch of indirect blocks for
Direct I/O, controllable via all the same mechanisms.

Signed-off-by:	Alexander Motin <mav@FreeBSD.org>
Sponsored by:	iXsystems, Inc.
Fixes #17027
Reviewed-by: Rob Norris <robn@despairlabs.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
2025-05-13 14:26:55 -07:00
.github ZTS: Optimize KSM on Linux and remove it for FreeBSD 2025-04-29 15:27:47 -04:00
cmd Wire O_DIRECT also to Uncached I/O (#17218) 2025-05-13 14:26:55 -07:00
config Support using llvm-libunwind 2025-04-24 13:58:48 -04:00
contrib Introduce zfs rewrite subcommand (#17246) 2025-05-12 10:22:17 -07:00
etc SPDX: license tags: MIT 2025-03-13 17:56:54 -07:00
include Wire O_DIRECT also to Uncached I/O (#17218) 2025-05-13 14:26:55 -07:00
lib Wire O_DIRECT also to Uncached I/O (#17218) 2025-05-13 14:26:55 -07:00
man Wire O_DIRECT also to Uncached I/O (#17218) 2025-05-13 14:26:55 -07:00
module Wire O_DIRECT also to Uncached I/O (#17218) 2025-05-13 14:26:55 -07:00
rpm RPM: Hold back incompatible kernel packages on Fedora 2025-04-30 10:52:20 -07:00
scripts update_authors: output possible mailmap additions 2025-05-13 09:24:03 -07:00
tests Wire O_DIRECT also to Uncached I/O (#17218) 2025-05-13 14:26:55 -07:00
udev vdev_id: symlinks creation for multipath disk partitions (#17331) 2025-05-13 13:49:13 -07:00
.cirrus.yml Update FreeBSD CI images 2025-03-13 13:31:31 -04:00
.editorconfig Add an .editorconfig; document git whitespace settings 2020-01-27 13:32:52 -08:00
.gitignore Packaging: Auto-generate changelog during configure (#15528) 2023-11-16 08:58:47 -08:00
.gitmodules .gitmodules: link to openzfs github repository 2021-04-12 09:37:23 -07:00
.mailmap AUTHORS/mailmap: update with new contributors 2025-05-13 09:24:03 -07:00
AUTHORS AUTHORS/mailmap: update with new contributors 2025-05-13 09:24:03 -07:00
autogen.sh Ubuntu 22.04 integration: ShellCheck 2022-11-18 11:24:48 -08:00
CODE_OF_CONDUCT.md Documentation corrections 2022-12-22 11:34:28 -08:00
configure.ac SPDX: license tags: CDDL-1.0 2025-03-13 17:56:27 -07:00
copy-builtin copy-builtin: add hooks with sed/>> 2022-05-10 10:17:43 -07:00
COPYRIGHT Fix typos 2020-06-09 21:24:09 -07:00
LICENSE Update build system and packaging 2018-05-29 16:00:33 -07:00
Makefile.am spdxcheck: program to check SPDX license tags 2025-03-13 17:57:51 -07:00
META Linux 6.14 compat: META (#17098) (#17172) 2025-03-25 10:35:01 -07:00
NEWS Fix NEWS file 2020-08-26 21:44:41 -07:00
NOTICE Update build system and packaging 2018-05-29 16:00:33 -07:00
README.md FreeBSD: remove support for FreeBSD < 13.0-RELEASE (#16372) 2024-08-05 16:56:45 -07:00
RELEASES.md Update RELEASES.md LTS release to 2.2 2025-01-17 11:04:36 -05:00
TEST Remove CI builder customization from TEST 2020-03-16 10:46:03 -07:00
zfs.release.in Move zfs.release generation to configure step 2012-07-12 12:22:51 -07:00

img

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.

codecov coverity

Official Resources

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 META file contains the officially recognized supported Linux kernel versions.
  • Supported FreeBSD versions are any supported branches and releases starting from 13.0-RELEASE.