It is rather unexpected and seems worth mentioning. Reported in the community forum [0] and the explanation found by Alwin [1].
[0]: https://forum.proxmox.com/threads/123819/ [1]: https://serverfault.com/questions/1113127/fstrim-is-very-slow-on-xfs-and-always-return-same-value-unlike-ext4/1113129#1113129 Signed-off-by: Fiona Ebner <f.eb...@proxmox.com> --- qm.adoc | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/qm.adoc b/qm.adoc index bd535a2..3ba2a3c 100644 --- a/qm.adoc +++ b/qm.adoc @@ -1063,6 +1063,12 @@ operations that have the potential to write out zeros to the storage: On a thin provisioned storage, this can help to free up unused space. +NOTE: There is a caveat with ext4 on Linux, because it uses an in-memory +optimization to avoid issuing duplicate TRIM requests. Since the guest doesn't +know about the change in the underlying storage, only the first guest-trim will +run as expected. Subsequent ones, until the next reboot, will only consider +parts of the filesystem that changed since then. + Troubleshooting ^^^^^^^^^^^^^^^ -- 2.30.2 _______________________________________________ pve-devel mailing list pve-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
