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From: Roy Sigurd Karlsbakk <roy@karlsbakk.net>
To: linux-lvm <linux-lvm@redhat.com>
Cc: Håkon <hawken@thehawken.org>
Subject: Re: [linux-lvm] Looking ahead - tiering with LVM?
Date: Wed, 9 Sep 2020 21:41:20 +0200 (CEST)	[thread overview]
Message-ID: <695805084.5038574.1599680480630.JavaMail.zimbra@karlsbakk.net> (raw)
In-Reply-To: <3503b4f5b55345beb24de4b156ee75c7@assyoma.it>

>> First, filelevel is usually useless. Say you have 50 VMs with Windows
>> server something. A lot of them are bound to have a ton of equal
>> If you look at IOPS instead of just sequencial speed, you'll see the
>> difference. A set of 10 drives in a RAID-6 will perhaps, maybe, give
>> you 1kIOPS, while a single SSD might give you 50kIOPS or even more.
>> This makes a huge impact.
> 
> IOPs are already well server by LVM cache. So, I genuinely ask: what
> would be tiering advantage here? I'll love to ear a reasonable use case.

LVMcache only helps if the cache is there in the first place and IIRC it's cleared after a reboot. It help won't that much over time with large storage. It also wastes space.

Vennlig hilsen

roy
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Roy Sigurd Karlsbakk
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http://blogg.karlsbakk.net/
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Hið góða skaltu í stein höggva, hið illa í snjó rita.

  parent reply	other threads:[~2020-09-09 19:41 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-02 18:38 Roy Sigurd Karlsbakk
2020-09-05 11:47 ` Gionatan Danti
2020-09-09 15:01   ` Roy Sigurd Karlsbakk
2020-09-09 18:16     ` Gionatan Danti
2020-09-09 18:47       ` John Stoffel
2020-09-09 19:10         ` Zdenek Kabelac
2020-09-09 19:21           ` John Stoffel
2020-09-09 19:44         ` Gionatan Danti
2020-09-09 19:53           ` John Stoffel
2020-09-09 20:20             ` Gionatan Danti
2020-09-09 19:41       ` Roy Sigurd Karlsbakk [this message]
2020-09-09 19:49         ` Gionatan Danti

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