profiling data of lacking ICH2 (was: poor ATA disk speed with ICH2)
bkoenig at cs.tu-berlin.de
Fri Sep 10 16:14:18 PDT 2004
I built a recent GENERIC kernel (1.413.2.2 2004/09/09 23:10:48 scottl) with
high resolution kernel profiling (config -pp). I ran a little shell script
in single-user mode which looks like
dd if=/dev/zero of=/usr/out bs=4096 count=262144
and created the following output with gprof:
(I'm sorry for posting this external link, but I didn't like to append
~15000 lines to this mail ;-)
This is my dmesg:
The dd command told ~15 MB/s without profiling (~500 kB/s with profiling).
There is absolutely no failure with the hard disk and the controller,
because after that I installed a 4.10-RELEASE into the same slice and it
works pretty fine (~37 MB/s). I repeated this test at another position on
hard disk _completely_ ... and as expected I got similar results.
I hope the profiling data helps. I would like to see a gprof output of a
system which works correctly, otherwise I have no possibility to compare. I
have the time and motivation to analyse them and point out the difference.
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