5 Feb
2020
5 Feb
'20
12:44 p.m.
Hi,
This helped to disable deferred writes in my case:
bluestore_min_alloc_size=4096
bluestore_prefer_deferred_size=0
bluestore_prefer_deferred_size_ssd=0
If you already deployed your OSDs with min_alloc_size=4K then you don't
need to redeploy them again.
> Hi Vitality,
>
> I completely destroyed the test cluster and re-deployed it after
> changing these settings but it did not make a difference - there are
> still a high number of deferred writes.
>
> Regards
> --
> Brad.
>
> On Wed, 5 Feb 2020 at 10:55, <vitalif(a)yourcmc.ru> wrote:
>
>> min_alloc_size can't be changed after formatting an OSD, and yes,
>> bluestore defers all writes that are < min_alloc_size. And default
>> min_alloc_size_ssd is 16KB.