Forgot to mention - this was on a rather crusty 4.2.6 kernel. Just upgraded to 4.8.1 and the issue appears to have been resolved... On 10/18/2016 12:42 -0500, Walberg, Tim wrote: >> Unless I'm misinterpreting something it appears that maybe btrfs doesn't pass >> fstrim commands down to the underlying drives when being used in a RAID-1 config. >> >> I have this output from a small script I wrote to run at boot time (and also via >> cron.weekly), rather than using continous trim in the boot options: >> >> # cat /var/log/trim.log >> Thu Oct 13 07:40:07 CDT 2016 >> /boot: 454 MiB (476062720 bytes) trimmed >> >> Thu Oct 13 07:40:08 CDT 2016 >> /: 8.9 GiB (9585152000 bytes) trimmed >> >> Thu Oct 13 07:40:22 CDT 2016 >> /btrfs/0: 0 B (0 bytes) trimmed >> >> /boot and / are mdraid RAID 1 on partitions 1 and 3 of two Samsung 850 Pro SSDs. >> /btrfs/0 is a btrfs-raid RAID 1 of partition 4 on the same two drives. The btrfs >> case does not seem to accomplish anything. By comparison, I have the same drive >> in my laptop, but just a single one, and the non-btrfs-raid-1 file system on one >> of its partitions does run fstrim successfully. >> >> This is quite possibly a known limitation, but I didn't find anything about it >> through some quick searching. Maybe I didn't dive deep enough... >> >> -- >> twalberg@xxxxxxxxx, twalberg@xxxxxxxxxxx >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html End of included message -- twalberg@xxxxxxxxx, twalberg@xxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
