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From: Zdenek Kabelac <zkabelac@redhat.com>
To: LVM general discussion and development <linux-lvm@redhat.com>,
	Dale Stephenson <dalestephenson@mac.com>
Subject: Re: [linux-lvm] Performance penalty for 4k requests on thin provisioned volume
Date: Thu, 14 Sep 2017 13:13:41 +0200	[thread overview]
Message-ID: <56cdaa13-a10a-a545-3cb6-cb454330df3f@redhat.com> (raw)
In-Reply-To: <c8762bcf-4db5-973e-e5d2-4683e4076351@assyoma.it>

Dne 14.9.2017 v 12:57 Gionatan Danti napsal(a):
> On 14/09/2017 11:37, Zdenek Kabelac wrote:
>> Sorry my typo here - is NOT ;)
>>
>>
>> Zdenek
> 
> Hi Zdenek,
> as the only variable is the LVM volume type (fat/thick vs thin), why the thin 
> volume is slower than the thick one?
> 
> I mean: all other things being equal, what is holding back the thin volume?



So few more question:

What is '/dev/sdb4'  ? - is it also some fast SSD ?

([thinpool_tmeta] volgr0 ewi-ao----  16.00g  1     0  /dev/sdb4:0-4095
  - just checking to be sure your metadata device is not placed on rotational 
storage device)...

What is your thin-pool chunk size - is it 64K ?
- if your raise thin-pool chunk size up - is it getting any better ?


Regards

Zdenek

  reply	other threads:[~2017-09-14 11:13 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-09-13 15:33 [linux-lvm] Performance penalty for 4k requests on thin provisioned volume Dale Stephenson
2017-09-13 20:19 ` Zdenek Kabelac
2017-09-13 22:39   ` Dale Stephenson
2017-09-14  9:00     ` Zdenek Kabelac
2017-09-14  9:37       ` Zdenek Kabelac
2017-09-14 10:52         ` Gionatan Danti
2017-09-14 10:57         ` Gionatan Danti
2017-09-14 11:13           ` Zdenek Kabelac [this message]
2017-09-14 14:32             ` Dale Stephenson
2017-09-14 15:25       ` Dale Stephenson

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