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From: Gionatan Danti <g.danti@assyoma.it>
To: Zhiyong Ye <yezhiyong@bytedance.com>
Cc: LVM general discussion and development <linux-lvm@redhat.com>
Subject: Re: [linux-lvm] Why is the performance of my lvmthin snapshot so poor
Date: Wed, 15 Jun 2022 11:34:00 +0200	[thread overview]
Message-ID: <31a7b7e9ea9e60fe42d93f6f113fcaf0@assyoma.it> (raw)
In-Reply-To: <d354dfb0-c37e-8a85-6cf6-d4b3a7e9257d@bytedance.com>

Il 2022-06-15 09:42 Zhiyong Ye ha scritto:
> I regenerated the thin volume with the chunksize of 64K and the random
> write performance data tested with fio 64k requests is as follows:
> case                    iops
> thin lv                 9381
> snapshotted thin lv     8307

As expected, increasing I/O size (to avoid r/m/w) greatly reduced the 
issue (the ~11% hit is due to metadata allocation overhead).

I don't see anything wrong, so I think you had to live with the 
previously recorded 10x performance hit when overwriting 4K blocks on a 
64K chunk size thin volume...

Regards.

-- 
Danti Gionatan
Supporto Tecnico
Assyoma S.r.l. - www.assyoma.it
email: g.danti@assyoma.it - info@assyoma.it
GPG public key ID: FF5F32A8

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  reply	other threads:[~2022-06-15  9:34 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-06-13  8:49 [linux-lvm] Why is the performance of my lvmthin snapshot so poor Zhiyong Ye
2022-06-14  7:04 ` Gionatan Danti
2022-06-14 10:16   ` Zhiyong Ye
2022-06-14 12:56     ` Gionatan Danti
2022-06-14 13:29       ` Zhiyong Ye
2022-06-14 14:54         ` Gionatan Danti
2022-06-15  7:42           ` Zhiyong Ye
2022-06-15  9:34             ` Gionatan Danti [this message]
2022-06-15  9:46               ` Zhiyong Ye
2022-06-15 12:40                 ` Gionatan Danti
2022-06-15 16:39                   ` Demi Marie Obenour
2022-06-16  7:53             ` Demi Marie Obenour
2022-06-16 13:22               ` Gionatan Danti
2022-06-16 16:19                 ` Demi Marie Obenour
2022-06-16 19:50                   ` Gionatan Danti

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