Very Computer

Hi!

I used the disk I/O measurement programs in the distribution (FreeBSD
2.2.5 Release) to check the performance. The result was ~2MB/s which I
belive that for a machine with Adaptec 2940AU and a pretty fast disk, is
not the optimal result, correct?

In Linux you can use the hdparm tool to both check and tune the settings
so that you get better disk I/O. I'm sure there are similar things for
our great system too. If anybody could explain how to do it, or post
some pointers to info about this, I would really appreciate it.

--
Med v?nlig h?lsning, Yours

Joachim Str?mbergson - Alltid i harmonisk sv?ngning
---------------- Ericsson Microwave Systems AB -----------------
Joachim Str?mbergson            http://www.ericsson.se/microwave
     ASIC System on Silicon engineer, nice to CUTE animals.    
* Opinions above, expressed or implicit, are strictly personal *

Are you talking about raw disk performance or file system performance?
What program did you use?
What are the exact performace data for your disk? Is it SCSI I, II,
Ultra-SCSI, Wide-SCSI...?
What does `dd if=/dev/rsd0c of=/dev/null bs=16k count=1000' report?
What does `iozone' report?
Did you perhaps specify an interleave factor other than 1 or
enable rotational delays? (Head of the output of dumpfs might
be helpful)
Are any SCSI errors reported? What are the boot messages when
the kernel probes for controller and disks?

Give us some more input and somebody might be able to help you.

Quote:> In Linux you can use the hdparm tool to both check and tune the settings
> so that you get better disk I/O. I'm sure there are similar things for
> our great system too. If anybody could explain how to do it, or post
> some pointers to info about this, I would really appreciate it.

Some general information sources are

  man scsi
  less /usr/share/misc/scsi_modes
  man dumpfs
  man tunefs
  man disklabel

Hope this helps

Olaf
--
/\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\


|| D-12157 Berlin        | phone: +49 30  85 60 26 70            |
|| Germany / Deutschland | fax:   +49 30  85 60 26 71            |
\/////////////////////////////////////////////////////////////////