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Date: Fri, 10 Aug 2018 17:28:11 +0300
From: Paul <devgs@ukr.net>
Subject: Question regarding relevance of syncer(4) in the context of ZFS
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Hello team,


If my understanding is correct then ZFS does not need to be pushed around and being told when to sync data to devices.
It is perfectly capable of keeping data consistent and synchronized according to configured options.

We even disable 'sync' option of file system that we use. But unfortunately we see a constant and periodical spikes 
of load on our servers that are directly related to wake-ups of 'syncer' kernel daemon. Is it safe to assume that
'syncer' is not necessary on configurations that only use ZFS, and no other file systems? And hence, is it safe
to assume that setting all of 'kern.filedelay', 'kern.dirdelay' and 'kern.metadelay' to some large values will not 
compromise system's durability?

Best regards,
Paul