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Date: Thu, 12 May 2011 11:33:27 +0300
From: Daniel Kalchev <daniel@digsys.bg>
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Subject: Re: ZFS: How to enable cache and logs.
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On 12.05.11 11:02, =8Aimun Mikecin wrote:
>
> You will not find a rotating hard drive that has a write latency anythi=
ng near the write latency of even a slowest SSD you can find on the marke=
t.
>
Cheap SSDs do not have acceptable latency, when saturated with writes.=20
Not to speak of throughput.

Truth is, SLOG should be on write-optimized SLC SSD. Any tricks, such as =

compression, manufacturers make with consumer products do influence=20
Windows benchmarks, but are unlikely to change laws of physics.

For most small installs, using rotating magnetic media (cheap!) as SLOG, =

can have dramatic performance improvement compared to not using any SLOG.=


Daniel