ATA disk performance (ICH2 controller), some tests and
comparison with Linux 2.6.5
frode at nordahl.net
Sat Sep 25 14:42:43 PDT 2004
On Sep 25, 2004, at 22:59, Mauro Triulzi wrote:
> b) Now the same under Linux (kernel 2.6.5)
> Write performance
> linux:/usr # date && dd if=/dev/zero of=deleteme.now count=1000000 &&
> Sat Sep 25 21:38:30 CEST 2004
> 1000000+0 records in
> 1000000+0 records out
> Sat Sep 25 21:38:35 CEST 2004
> deleteme.now is about 488 MB, rate about 100 MB/sec!!
I'm pretty sure you have more than 488 MB memory, so the data will
never actually be written to disk during this test. You should write a
file at least twice the size of your memory, and rerun it three times
to get any good results, running sync immedialtely after the dd will
not hurt neither.
In general, your test is obviously run on a disk in a multiboot
situation, this will not work. As FreeBSD and Linux will be put on
different parts of the disk which has different characteristics when it
comes to available performance.
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