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Subject: Re: ZFS performance bottlenecks: CPU or RAM or anything else?
From: Daniel Kalchev <daniel@digsys.bg>
In-Reply-To: <16e474da-6b20-2e51-9981-3c262eaff350@lexa.ru>
Date: Tue, 17 May 2016 15:29:20 +0300
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To: Alex Tutubalin <lexa@lexa.ru>
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> On 17.05.2016 =D0=B3., at 15:21, Alex Tutubalin <lexa@lexa.ru> wrote:
>=20
> On 5/17/2016 3:11 PM, InterNetX - Juergen Gotteswinter wrote:
>> Raidz is your Problem, go for Mirrors
>=20
> Raidz2 will survive two (any) drives failure, while mirrored stripe =
will not.
>=20

Not true. You can have N-way mirror and it will survive N-1 drive =
failures.

> So, if it is possible to increase raidz2 performance by faster CPU or =
RAM I'll go this route

The limitations of RAIDZ performance do not come from CPU or RAM =
limitations, but by the underlying hardware. RAIDZ is limited to the =
performance of a single disk IOPS.=20

CPU/RAM these days are so much faster than spinning disks or SSDs.

Daniel=