On 2018/11/22 下午10:03, Roman Mamedov wrote:
> On Thu, 22 Nov 2018 22:07:25 +0900
> Tomasz Chmielewski <t...@virtall.com> wrote:
>
>> Spot on!
>>
>> Removed "discard" from fstab and added "ssd", rebooted - no more
>> btrfs-cleaner running.
>
> Recently there has been a bugfix for TRIM in Btrfs:
>
> btrfs: Ensure btrfs_trim_fs can trim the whole fs
> https://patchwork.kernel.org/patch/10579539/
>
> Perhaps your upgraded kernel is the first one to contain it, and for the first
> time you're seeing TRIM to actually *work*, with the actual performance impact
> of it on a large fragmented FS, instead of a few contiguous unallocated areas.
>
That only affects btrfs_trim_fs(), and you can see it's only called from
ioctl interface, so it's definitely not the case.
Thanks,
Qu
