mergerfs v2.41.0

[trapexit]

https://github.com/trapexit/mergerfs/releases/tag/2.41.0

Despite the changelog not seeming too large there was a lot of internal reorganization and cleanup in preparation for these and future features. I tried to test the release to ensure no bugs or backwards compatibility issues (outside of some changes to some default values) but given the diversity and quantity of changes I could have missed something. Please submit a ticket if you find any problems: https://trapexit.github.io/mergerfs/latest/support/

Major Changes and New Features

• IO passthrough - Near native read/write performance (on supported Linux versions, read docs for limitations.)
• IO priority proxying - When performing file IO use the same IO priority as the requesting app.
• create policy default changed from epmfs to pfrd.
• Full rework of documentation: https://trapexit.github.io/mergerfs/
• Updated default inode calculation to make it more stable across reboots.
• Improved secondary group cache which will expire over time and can be cleared as needed.
• nofail mount argument passthrough
• mergerfs will now set its oom_score_adj value to reduce likelihood of being killed by OOM killer.
• statx support (allows for btime to be queried)

Other Changes

• Lots of internal improvements and restructuring.
• Addition of fsck.mergerfs and mergerfs.collect-info tools.
• Enable auto mmap enablement when using cache.files=off (not relevant when io passthrough is used)
• Support for more than 256 page sized FUSE messages (not relevant when io passthrough is used)
• Ability to wait for branches to mount
• Improved config / option management allowing FUSE and mount options to be placed in a config file.
• Changes which improve performance when using xattrs and cache.files!=off (not relevant when io passthrough is used)
• More logging and details to syslog (available via journalctl -t mergerfs where used)

Full Git Log

• Suggest cache.files=auto-full rather than partial by @trapexit in Suggest cache.files=auto-full rather than partial #1320
• Add support for 'direct-io-allow-mmap' if supported by kernel by @trapexit in Add support for 'direct-io-allow-mmap' if supported by kernel #1321
• Update README.md by @techie2000 in Update README.md #1342
• Add missing --relative flag to rsync in percent-full mover script by @grunthos503 in Add missing --relative flag to rsync in percent-full mover script #1346
• Add FAQ entry on 'move' and 'copy' by @trapexit in Add FAQ entry on 'move' and 'copy' #1377
• add mkdocs first draft by @oregonpillow in add mkdocs first draft #1382
• Rework mkdocs based documentation by @trapexit in Rework mkdocs based documentation #1386
• Fix pip install in mkdocs workflow by @trapexit in Fix pip install in mkdocs workflow #1387
• Update README to point to docs, update project comparisons by @trapexit in Update README to point to docs, update project comparisons #1388
• Update funding and cirrus builds by @trapexit in Update funding and cirrus builds #1389
• Add tiered cache details to docs by @trapexit in Add tiered cache details to docs #1390
• Move fuse.c and fuse_lowlevel.c to C++ by @trapexit in Move fuse.c and fuse_lowlevel.c to C++ #1391
• Send invalidate node request outside lock by @trapexit in Send invalidate node request outside lock #1392
• fix edit uri by @oregonpillow in fix edit uri #1395
• Improve FreeBSD compatibility by @trapexit in Improve FreeBSD compatibility #1398
• Readability changes to mkdocs installation by @oregonpillow in Readability changes to mkdocs installation #1399
• Doc and mover script updates by @trapexit in Doc and mover script updates #1402
• Misc doc updates by @trapexit in Misc doc updates #1407
• Add details about user namespacing and root squashing by @trapexit in Add details about user namespacing and root squashing #1408
• Add details about logging to syslog by @trapexit in Add details about logging to syslog #1409
• Rework questions on what settings and policies to use by @trapexit in Rework questions on what settings and policies to use #1412
• Update quickstart.md by @theHenMan in Update quickstart.md #1413
• Update terminology.md by @theHenMan in Update terminology.md #1414
• Update docs on out-of-band usage by @trapexit in Update docs on out-of-band usage #1415
• Add FAQ section on common perceived problems by @trapexit in Add FAQ section on common perceived problems #1416
• Add FAQ entry regarding inotify by @trapexit in Add FAQ entry regarding inotify #1423
• Misc doc updates by @trapexit in Misc doc updates #1425
• Misc doc updates by @trapexit in Misc doc updates #1426
• Update docs on default create policy by @trapexit in Update docs on default create policy #1429
• Add links to options docs page to individual pages by @trapexit in Add links to options docs page to individual pages #1431
• Support Linux v6.13 FUSE max_page_limit by @trapexit in Support Linux v6.13 FUSE max_page_limit #1433
• Change misc defaults by @trapexit in Change misc defaults #1434
• Replace usage of wyhash with rapidhash by @trapexit in Replace usage of wyhash with rapidhash #1435
• Update docs regarding error handling by @trapexit in Update docs regarding error handling #1438
• Add statx support by @trapexit in Add statx support #1439
• Add doc pages for minfreespace and moveonenospc + other misc updates by @trapexit in Add doc pages for minfreespace and moveonenospc + other misc updates #1441
• Change the "devino" inode calculation by @trapexit in Change the "devino" inode calculation #1443
• Add FAQ entry regarding OS support by @trapexit in Add FAQ entry regarding OS support #1444
• Misc doc updates + add logo by @trapexit in Misc doc updates + add logo #1445
• Improve mount waiting + misc doc improvements by @trapexit in Improve mount waiting + misc doc improvements #1447
• Add config option to control default_permissions by @trapexit in Add config option to control default_permissions #1448
• Fixed a minor typo by @Solipsistmonkey in Fixed a minor typo #1450
• Rework thread pool for increased stability + config and doc updates by @trapexit in Rework thread pool for increased stability + config and doc updates #1453
• Add podman release build tooling + misc build fixes by @trapexit in Add podman release build tooling + misc build fixes #1455
• Update installation.md for SUSE by @gizak in Update installation.md for SUSE #1449
• Add versioning to docs using 'mike' by @trapexit in Add versioning to docs using 'mike' #1456
• Add details to docs about FreeBSD limitations by @trapexit in Add details to docs about FreeBSD limitations #1457
• Update README.md to fix link by @trapexit in Update README.md to fix link #1464
• Rework policies to return branches rather than path strings by @trapexit in Rework policies to return branches rather than path strings #1466
• Fix incorrect dyn cast by @trapexit in Fix incorrect dyn cast #1467
• Add debugging of mutexes by @trapexit in Add debugging of mutexes #1470
• Add support for FUSE passthrough by @trapexit in Add support for FUSE passthrough #1472
• Misc cleanup by @trapexit in Misc cleanup #1473
• Spawn "mount" on branches when waiting for mounts enabled by @trapexit in Spawn "mount" on branches when waiting for mounts enabled #1476
• Misc doc updates by @trapexit in Misc doc updates #1477
• Add RHEL/CentOS 10 build support by @trapexit in Add RHEL/CentOS 10 build support #1479
• Add fsck.mergerfs tool by @trapexit in Add fsck.mergerfs tool #1483
• Set default read thread count to 0 by @trapexit in Set default read thread count to 0 #1484
• Remove linux only getdents in favor of readdir for FreeBSD sake by @trapexit in Remove linux only getdents in favor of readdir for FreeBSD sake #1485
• Misc cleanup by @trapexit in Misc cleanup #1486
• Rework movefile and cow break to use copyfile by @trapexit in Rework movefile and cow break to use copyfile #1488
• Misc documentation changes by @trapexit in Misc documentation changes #1489
• Add mergerfs.collect-info by @trapexit in Add mergerfs.collect-info #1491
• Update the secondary group cache by @trapexit in Update the secondary group cache #1492
• Ensure passthrough and keep_cache are mutually exclusive by @trapexit in Ensure passthrough and keep_cache are mutually exclusive #1493
• Clear O_NOFOLLOW when opening a relative fd by @trapexit in Clear O_NOFOLLOW when opening a relative fd #1494
• Rework of runtime interface by @trapexit in Rework of runtime interface #1498
• Move everything to negative errno return types by @trapexit in Move everything to negative errno return types #1499
• Cleanup copy functions by @trapexit in Cleanup copy functions #1500
• Build improvements by @trapexit in Build improvements #1501
• More makefile tweaks, build log, smaller git clones by @trapexit in More makefile tweaks, build log, smaller git clones #1503
• Add setting of oom_score_adj by @trapexit in Add setting of oom_score_adj #1504
• Misc documentation updates by @trapexit in Misc documentation updates #1505
• Add Debian 13 build targets by @trapexit in Add Debian 13 build targets #1506
• Rework calculation of branch for release make targets by @trapexit in Rework calculation of branch for release make targets #1507
• Fix constructing string from attrval setxattr config by @trapexit in Fix constructing string from attrval setxattr config #1508
• Allow empty lines in config ini files by @Max-F-Helm in Allow empty lines in config ini files #1509
• Updates to docs, add nonraid, more intro to fs details by @trapexit in Updates to docs, add nonraid, more intro to fs details #1512
• Misc changes by @trapexit in Misc changes #1513
• Fix string manipulation functions after refactor by @trapexit in Fix string manipulation functions after refactor #1514
• Update readme to match index of mkdocs by @trapexit in Update readme to match index of mkdocs #1515
• More build process updates by @trapexit in More build process updates #1516
• Misc updates of docs by @trapexit in Misc updates of docs #1518
• Add Ubuntu 25.04 builds by @trapexit in Add Ubuntu 25.04 builds #1519
• Revert removal of readdir init setup, simplify cfg usage by @trapexit in Revert removal of readdir init setup, simplify cfg usage #1520
• Use std::filesystem::path for fusepath by @trapexit in Use std::filesystem::path for fusepath #1522
• idmap mount support by @trapexit in idmap mount support #1523
• Misc docs updates by @trapexit in Misc docs updates #1524
• Fix broken doc links by @trapexit in Fix broken doc links #1525
• Update moveonenospc.md by @pjv in Update moveonenospc.md #1527
• Add script to generate docs from scratch and push to github by @trapexit in Add script to generate docs from scratch and push to github #1530
• Misc doc updates by @trapexit in Misc doc updates #1531
• Fix typo in visualization and add new vid to docs by @trapexit in Fix typo in visualization and add new vid to docs #1532
• Add getdents based readdir functions for Linux by @trapexit in Add getdents based readdir functions for Linux #1533
• Add ability to proxy ioprio of client apps by @trapexit in Add ability to proxy ioprio of client apps #1534
• Remove need for and use of ioprio header by @trapexit in Remove need for and use of ioprio header #1535
• Misc fixes, mostly for FreeBSD by @trapexit in Misc fixes, mostly for FreeBSD #1536
• Misc build fixes by @trapexit in Misc build fixes #1537
• Fix dirent64::namelen calculation by @trapexit in Fix dirent64::namelen calculation #1538
• Fix rename path generation by @trapexit in Fix rename path generation #1540
• Make allow-idmap optional (default: false) by @trapexit in Make allow-idmap optional (default: false) #1541
• Allow setting of passthrough max-stack-depth by @trapexit in Allow setting of passthrough max-stack-depth #1542
• Rework how fuse request context is handled by @trapexit in Rework how fuse request context is handled #1543
• Misc docs updates by @trapexit in Misc docs updates #1544
• Rework config, centralize fuse config by @trapexit in Rework config, centralize fuse config #1547
• Misc docs updates by @trapexit in Misc docs updates #1549
• Fix lack of include for fmt by @trapexit in Fix lack of include for fmt #1550
• Config options docs updates by @trapexit in Config options docs updates #1551
• Update fuse-msg-size docs by @trapexit in Update fuse-msg-size docs #1552
• Fix variable names of fuse-msg-size and posix-acl by @trapexit in Fix variable names of fuse-msg-size and posix-acl #1553
• Misc updates to arg parsing by @trapexit in Misc updates to arg parsing #1554
• Fix manpage links for 2.41.0-rc3 by @satmandu in Fix manpage links for 2.41.0-rc3 #1555
• Add more debugging options to makefiles and cleanup by @trapexit in Add more debugging options to makefiles and cleanup #1556
• Mention how mmap error when direct io is enabled by @trapexit in Mention how mmap error when direct io is enabled #1557
• Further tweaks to config parsing and error reporting by @trapexit in Further tweaks to config parsing and error reporting #1559
• Improve mergerfs intro in docs by @trapexit in Improve mergerfs intro in docs #1563
• Ensure backward compatibility with remember & noforget by @trapexit in Ensure backward compatibility with remember & noforget #1566
• Add ability to passthrough 'nofail' mount option by @trapexit in Add ability to passthrough 'nofail' mount option #1567
• Add container image building by @trapexit in Add container image building #1568
• Add container image details by @trapexit in Add container image details #1569

New Contributors

• @techie2000 made their first contribution in Update README.md #1342
• @oregonpillow made their first contribution in add mkdocs first draft #1382
• @theHenMan made their first contribution in Update quickstart.md #1413
• @Solipsistmonkey made their first contribution in Fixed a minor typo #1450
• @gizak made their first contribution in Update installation.md for SUSE #1449
• @Max-F-Helm made their first contribution in Allow empty lines in config ini files #1509
• @pjv made their first contribution in Update moveonenospc.md #1527
• @satmandu made their first contribution in Fix manpage links for 2.41.0-rc3 #1555

Full Changelog: 2.40.2...2.41.0

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This discussion was created from the release 2.41.0.