[27182] in Athena Bugs
linux 9.4.46: kernel
daemon@ATHENA.MIT.EDU (Ken T Takusagawa)
Tue Feb 12 23:18:14 2008
Message-Id: <200802130417.m1D4Hw8F004206@m37-332-8.mit.edu>
To: bugs@mit.edu
Date: Tue, 12 Feb 2008 23:17:58 -0500
From: Ken T Takusagawa <kenta@mit.edu>
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System name: m37-332-8.mit.edu
Type and version: i686 9.4.46
Display type: ATI Technologies Inc RV516 [Radeon X1300/X1550 Series]
Shell: /bin/athena/bash
Window manager: sawfish
What were you trying to do?
Run programs which are hard disk intensive (local hard disk)
What's wrong:
Athena Linux (in particular on the new Dell Optiplex 745)
has horrible hard drive performance. For example:
$ time dd if=/dev/zero of=/tmp/test bs=1M count=1024
1024+0 records in
1024+0 records out
real 1m34.918s
user 0m0.001s
sys 0m5.738s
# hdparm -tT /dev/hda
/dev/hda:
Timing cached reads: 4220 MB in 2.00 seconds = 2110.32 MB/sec
Timing buffered disk reads: 12 MB in 3.20 seconds = 3.76 MB/sec
I installed Debian Etch (i686, ext3 Filesystem, kernel 2.6.18-6-686)
on the same hardware and got:
$ time dd if=/dev/zero of=/tmp/test bs=1M count=1024
1024+0 records in
1024+0 records out
1073741824 bytes (1.1 GB) copied, 4.04747 seconds, 265 MB/s
real 0m4.074s
user 0m0.000s
sys 0m2.012s
$ sudo hdparm -tT /dev/sda
/dev/sda:
Timing cached reads: 6680 MB in 2.00 seconds = 3342.88 MB/sec
Timing buffered disk reads: 242 MB in 3.03 seconds = 79.95 MB/sec
I was able to replicate these results on two machines. There is a
23x speed difference in the "dd" test, and 21x difference in the
"buffered disk reads" hdparm test.
What should have happened:
Please describe any relevant documentation references:
See also /mit/sipbzlog/sbi/athena on the conversation starting on
Tue Feb 12 22:20:54 2008
