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Date: Sun, 11 Oct 2020 22:15:33 +0200
From: Bastian Blank <bblank@thinkmo.de>
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Subject: Re: [linux-lvm] raid0 - no performance increase??
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To: linux-lvm@redhat.com

On Sat, Oct 10, 2020 at 05:52:32PM +0100, lejeczek wrote:
> I have a simple raid0 lvm comprising of two NVME devices.
> I'd expect performance of such a volume to be higher than a
> "regular" volume ran of a single NVME, but simple dbench
> shows such raid0 volume to the same "slow" as a single NVME
> volume.

Why do you think?  What is dbench anyway?  Linear access is not going to
be faster, as it is dominated by latency.  Please use fio with _random_
reads or writes and a useful queue depth.

Also, what do you mean with slow?  500k IOPS?

Bastian

-- 
War is never imperative.
		-- McCoy, "Balance of Terror", stardate 1709.2