linux-lvm.redhat.com archive mirror
 help / color / mirror / Atom feed
From: Daniel Janzon <daniel.janzon@edgeware.tv>
To: "linux-lvm@redhat.com" <linux-lvm@redhat.com>
Subject: Re: [linux-lvm] linux-lvm Digest, Vol 190, Issue 6
Date: Tue, 10 Dec 2019 09:24:28 +0000	[thread overview]
Message-ID: <A8A53B0E4B7ACF4BAD5C77D3671AC8976ABE96EE@EX01.edgeware.tv> (raw)
In-Reply-To: <mailman.48461.1575969111.11187.linux-lvm@redhat.com>

> From: Marian Csontos <mcsontos@redhat.com>

>> The origin of my problem is indeed the poor performance of RAID5,
>> which maxes out the single core the driver runs on. But if I accept that
>> as a given, the next problem is LVM striping. Since I do get 10x better

>What stripesize was used for striped LV? IIRC the default is 64k.

I ran  "lvcreate -L 2400G -i8 -I512 -n volume-name group-name".  And I tried various numbers, 512 was the greatest I could set but does not seem to be crucial for performance.

> IIUC you are serving mostly large files. I have no numbers, and no HW to
> test the hypothesis, but using larger stripesize could help here as this
> would split the load on multiple RAID5 volumes, while not splitting the
> IOs too early into too many small requests.

File size are typically a few megabytes. I guess the file abstraction is not visible
on the LVM layer though, but at least there won't be many blocks with a lot
of unused space.

           reply	other threads:[~2019-12-10  9:24 UTC|newest]

Thread overview: expand[flat|nested]  mbox.gz  Atom feed
 [parent not found: <mailman.48461.1575969111.11187.linux-lvm@redhat.com>]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=A8A53B0E4B7ACF4BAD5C77D3671AC8976ABE96EE@EX01.edgeware.tv \
    --to=daniel.janzon@edgeware.tv \
    --cc=linux-lvm@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).