TRIM SSD

[flx5]

SSD write performance before trimming on /mnt/vm/ and nextcloud file system.

root@nas:/mnt/vm/libvirt# time dd if=/dev/zero of=tst.out bs=4M count=1024
1024+0 records in
1024+0 records out
4294967296 bytes (4.3 GB, 4.0 GiB) copied, 95.8851 s, 44.8 MB/s

real	1m35.888s
user	0m0.010s
sys	0m3.301s

After calling fstrim:

root@nas:/mnt/vm/libvirt# time dd if=/dev/zero of=tst.out bs=4M count=1024
1024+0 records in
1024+0 records out
4294967296 bytes (4.3 GB, 4.0 GiB) copied, 24.3756 s, 176 MB/s

real	0m24.379s
user	0m0.011s
sys	0m3.494s

Cronjob might be missing on the host: https://wiki.ubuntuusers.de/SSD/TRIM/#TRIM-mit-Festplattenverschluesselung
However every vm using lvm disks directly would also need to call trim (100 GB trimmed on nextcloud).

In my opinion the VMs aren't supposed to require knowledge of the underlying hardware. Need to find a solution.