linux-ext4 - Re: More testing: 4x parallel 2G writes, sequential reads

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-id: <473247A3.5020800@gmail.com>
Date:	Thu, 08 Nov 2007 02:17:55 +0300
From:	Alex Tomas <bzzz.tomas@...il.com>
To:	Eric Sandeen <sandeen@...hat.com>
Cc:	ext4 development <linux-ext4@...r.kernel.org>
Subject: Re: More testing: 4x parallel 2G writes, sequential reads

Hi,

could you try to larger preallocation? like 512/1024/2048 blocks, please?

thanks, Alex

Eric Sandeen wrote:
> I tried ext4 vs. xfs doing 4 parallel 2G IO writes in 1M units to 4
> different subdirectories of the root of the filesystem:
> 
> http://people.redhat.com/esandeen/seekwatcher/ext4_4_threads.png
> http://people.redhat.com/esandeen/seekwatcher/xfs_4_threads.png
> http://people.redhat.com/esandeen/seekwatcher/ext4_xfs_4_threads.png
> 
> and then read them back sequentially:
> 
> http://people.redhat.com/esandeen/seekwatcher/ext4_4_threads_read.png
> http://people.redhat.com/esandeen/seekwatcher/xfs_4_threads_read.png
> http://people.redhat.com/esandeen/seekwatcher/ext4_xfs_4_read_threads.png
> 
> At the end of the write, ext4 had on the order of 400 extents/file, xfs
> had on the order of 30 extents/file.  It's clear especially from the
> read graph that ext4 is interleaving the 4 files, in about 5M chunks on
> average.  Throughput seems comparable between ext4 & xfs nonetheless.
> 
> Again this was on a decent HW raid so seek penalties are probably not
> too bad.
> 
> -Eric
> -
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 

-
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html