ZFS... / scrub speed up

[Miroslav Lachman]

Miroslav Lachman wrote on 2019/05/09 13:36:
> Dimitry Andric wrote on 2019/05/09 13:02:
>> On 9 May 2019, at 10:32, Miroslav Lachman <000.fbsd at quip.cz> wrote:
> 
> [...]
> 
>>> Disks are OK, monitored by smartmontools. There is nothing odd, just 
>>> the long long scrubs. This machine was started with 4x 1TB (now 4x 
>>> 4TB) and scrub was slow with 1TB disks too. This machine - HP ML110 
>>> G8) was my first machine with ZFS. If I remember it well it was 
>>> FreeBSD 7.0, now running 11.2. Scrub was / is always about one week. 
>>> (I tried some sysctl tuning without much gain)
>>
>> Unfortunately https://svnweb.freebsd.org/changeset/base/339034, which
>> greatly speeds up scrubs and resilvers, was not in 11.2 (since it was
>> cut at r334458).
>>
>> If you could update to a more recent snapshot, or try the upcoming 11.3
>> prereleases, you will hopefully see much shorter scrub times.
> 
> Thank you. I will try 11-STABLE / 11.3-PRERELEASE soon and let you know 
> about the difference.

Little bit late because I run scrub once per 60 days. Now on FreeBSD 
11.3-RELEASE-p3 scrub takes 2 days and 10 hours instead of 1 week.
This is a great improvement!

Kind regards
Miroslav Lachman