linux-btrfs.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Michael <mclaud@roznica.com.ua>
To: linux-btrfs@vger.kernel.org
Subject: Re: Read-only snapshot send speed very slow after modify original data. Need help
Date: Wed, 6 Nov 2019 16:48:05 +0200	[thread overview]
Message-ID: <66dfd39b-7a40-0cce-0cbf-1b5ba1a629d1@roznica.com.ua> (raw)
In-Reply-To: <af5343ac-2896-51ef-18f5-de05498c01f9@roznica.com.ua>

30.10.2019 14:07, Michael пишет:
> Hi linux-btrfs,
>
> Step to reproduce
>
> 1) mkfs.btrfs -draid6 -mraid6 /dev/sd[abcdefgh]
>
> 2) mount 
> -onoatime,nodiratime,thread_pool=24,max_inline=0,ssd_spread,compress-force=zstd 
> /dev/sda /mnt/test/
>
> 3) btrfs subvol create /mnt/test/subvol/
>
> 4) dd if=/dev/zero of=/mnt/test/subvol/test.dat bs=1M count=65536
>
> 5) btrfs subvol snapshot -r /mnt/test/subvol /mnt/test/subvol.ro
>
> 6) btrfs send /mnt/test/subvol.ro | pv >/dev/null
>
> 64,1GiB 0:01:18 [ 833MiB/s]  - fast
>
> 7) for i in {1..16384}; do echo $i; printf '\x01\x02\x03' | dd 
> of=/mnt/test/subvol/test.dat bs=1 seek=$(($i * 1024 * 1024)) count=3 
> conv=notrunc; done
>
> 8) btrfs send /mnt/test/subvol.ro | pv >/dev/null
>
> I stop it at 0:01:18
>
> 464MiB 0:01:18 [4,67MiB/s] - very very slow
Does this problem concern me only?
>
>
> uname -a
> Linux storage.domain.com 5.3.7-200.fc30.x86_64 #1 SMP Fri Oct 18 
> 20:13:59 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
>


      parent reply	other threads:[~2019-11-06 14:48 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-30 12:07 Read-only snapshot send speed very slow after modify original data. Need help Michael
2019-10-30 12:38 ` Filipe Manana
2019-10-30 12:54   ` Michael
2019-11-06 14:48 ` Michael [this message]

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=66dfd39b-7a40-0cce-0cbf-1b5ba1a629d1@roznica.com.ua \
    --to=mclaud@roznica.com.ua \
    --cc=linux-btrfs@vger.kernel.org \
    /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).