From mboxrd@z Thu Jan  1 00:00:00 1970
From: Karsten Weiss <K.Weiss@science-computing.de>
Subject: Re: Bad ext4 sync performance on 16 TB GPT partition
Date: Fri, 26 Feb 2010 12:33:22 +0100 (CET)
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On Fri, 26 Feb 2010, Karsten Weiss wrote:

> However, the sync performance is fine if we ...
> 
> * use xfs or
> * disable the ext4 journal or
> * disable ext4 extents (but with enabled journal)

ext3 is okay, too:

# /usr/bin/time bash -c "dd if=/dev/zero of=/mnt/large/10GB_1 bs=1M count=10000 && sync"
10000+0 records in
10000+0 records out
10485760000 bytes (10 GB) copied, 39.7188 seconds, 264 MB/s
0.03user 21.00system 1:47.24elapsed 19%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+788minor)pagefaults 0swaps

Compare:

XFS:    57s
ext4: 7m26s

-- 
Karsten Weiss