https://fedoraproject.org/wiki/Changes/EnableFSTrimTimer == Summary == Enabling fstrim.timer will cause fstrim.service to execute weekly, which in turn executes `/usr/sbin/fstrim --fstab --verbose --quiet` == Owner == * Name: [[User:chrismurphy| Chris Murphy]] * Email: bugzilla(a)colorremedies.com == Detailed Description == Over time, some users experience slow downs in certain flash storage devices. This might be alleviated by issuing a periodic fstrim command to the mounted file system. Devices and file systems that don't support fstrim are unaffected. By enabling the existing fstrim.timer systemd unit file by default, will cause weekly execution of the fstrim.service. This service acts only on mounted filesystems listed in fstab. On supported hardware (e.g. most SD Card, SSD, and NVMe drives), LVM thin provisioned storage, and file systems (ext4, XFS, Btrfs, f2fs, but excluding FAT16/32), fstrim will inform underlying physical storage device's firmware about unused blocks. This hinting can make wear leveling and block erasure more efficient. The timer will execute Monday at 00:00 local time. If the system is inactive at this time, it will be run immediately upon becoming active again (upon wake from suspend, during or very soon after boot). Some devices do not support "queued trim" and there may be a brief (seconds) pause as the drive firmware acts upon command issuance. It's expected most users won't notice this. == Benefit to Fedora == This is an optimization to the storage stack, and may help improve performance and wear leveling for some devices. On LVM thin provisioned stacks, unused LV extents will be returned to the thin pool, reducing the likelihood of pool exhaustion. In a way, this is overdue on Fedora, as it's been the default behavior on other distributions for a while (at least Ubuntu and openSUSE). At least it has been well tested. == Scope == * Proposal owners:<br> Upon approval, submit a PR for fedora-release, modifying 90-default.preset to enable fstrim.timer * Other developers:<br> fstrim.timer is provided by util-linux, notify util-linux maintainer<br> https://bugzilla.redhat.com/show_bug.cgi?id=1785041 * Release engineering: [https://pagure.io/releng/issues #9116] * Policies and guidelines: N/A * Trademark approval: N/A == Upgrade/compatibility impact == fstrim.timer will be enabled on upgrade. An upgraded system should exhibit the same behaviors as a clean installed system. == How To Test == The low level function of systemd timers, fstrim.service, and fstrim command are well understood and tested already, all Fedora needs to test is that the timer is enabled following clean installation and upgrades:<br><br> Preliminaries: * Clean install Fedora 32, any edition or spin; or * Upgrade from Fedora 30 or Fedora 31, any edition or spin, to Fedora 32 Confirm: * Run `sudo systemctl list-timers` * Confirm `fstrim.timer` is listed under UNITS, and is next scheduled for Monday 00:00:00 * Anytime following the listed NEXT date+time, run `sudo systemctl status fstrim.timer` Example, should apply in all cases:<br> {{code|Dec 18 13:48:54 fmac.local systemd[1]: fstrim.service: Succeeded.}} Full example on a device with an SSD and filesystem supporting trim:<br> <pre> $ sudo systemctl status fstrim.service ● fstrim.service - Discard unused blocks on filesystems from /etc/fstab Loaded: loaded (/usr/lib/systemd/system/fstrim.service; static; vendor preset: disabled) Active: inactive (dead) since Wed 2019-12-18 13:48:54 MST; 15min ago Docs: man:fstrim(8) Process: 3870 ExecStart=/usr/sbin/fstrim --fstab --verbose --quiet (code=exited, status=0/SUCCESS) Main PID: 3870 (code=exited, status=0/SUCCESS) CPU: 1.387s Dec 18 13:48:48 fmac.local systemd[1]: Starting Discard unused blocks on filesystems from /etc/fstab... Dec 18 13:48:54 fmac.local fstrim[3870]: /: 32 GiB (34409328640 bytes) trimmed on /dev/sda4 Dec 18 13:48:54 fmac.local systemd[1]: fstrim.service: Succeeded. Dec 18 13:48:54 fmac.local systemd[1]: Started Discard unused blocks on filesystems from /etc/fstab. Dec 18 13:48:54 fmac.local systemd[1]: fstrim.service: Consumed 1.387s CPU time. </pre> <br> Regardless of configuration, there should be no errors. == User Experience == Most users will not notice the change. Some will notice improved performance of flash storage devices, and more efficient use of thinly provisioned storage. This does not affect all storage. Only file systems listed in fstab are affected. If the user/admin wants fstrim to apply to all mounted file systems, they should copy the original fstrim.service unit file, replacing `--fstab` with `--all`, and use this modified unit file as a drop-in service unit in /etc. See https://www.freedesktop.org/software/systemd/man/systemd.unit.html == Dependencies == None == Contingency Plan == * Contingency mechanism: Owner will revert the change * Contingency deadline: final freeze * Blocks release? No * Blocks product? No == Documentation == man fstrim == Release Notes == fstrim.timer is enabled by default, and runs fstrim.service weekly. This service executes `/usr/sbin/fstrim --fstab --verbose --quiet` See `man fstrim` for details. -- Ben Cotton He / Him / His Fedora Program Manager Red Hat TZ=America/Indiana/Indianapolis