RE: Kenwood/Hi-Val True-X 40x CDROM drive.

Mike A. Harris (mharris@ican.net)
Tue, 4 May 1999 04:51:57 -0400 (EDT)

On Tue, 4 May 1999, BROWN Nick wrote:

>I've given up on hdparm. With my generic IDE disk, I get 8 MB/sec, and
>about 22 MB/sec if I read from the cache.

I get:

2 root@red:/# hdparm -tT /dev/hd[ab]

/dev/hda:
Timing buffer-cache reads: 64 MB in 1.69 seconds =37.87 MB/sec
Timing buffered disk reads: 32 MB in 3.29 seconds = 9.73 MB/sec

/dev/hdb:
Timing buffer-cache reads: 64 MB in 1.67 seconds =38.32 MB/sec
Timing buffered disk reads: 32 MB in 5.01 seconds = 6.39 MB/sec

>With my 7200 rpm SCSI disks (OK, SCSI-2, not SCSI-3, but
>still...), I get between 1.8 and 3.5 MB/sec (depending on wind
>direction, it seems) reading the disk, and 25 to 33 MB/sec
>reading the cache (which presumably means it's not the
>controller being slower than IDE).

My hdparm results seem very indicative of actual transfer rates
for IDE disks.

>Meanwhile my own informal benchmarks (copy from /dev/xdx to /dev/null) show
>the SCSI disks to be slightly faster than the IDE disk, which seems
>reasonable. Are the hdparm numbers from the same school of thought that
>gave us bogoMIPs ?

If you copy as described above, are you rebooting inbetween
tests, or otherwise somehow emptying any cached data? Just a
thought...

TTYL

--
Mike A. Harris                   Linux advocate      GNU advocate
Computer Consultant                          Open Source advocate  


The DVORAK keyboard layout RULES!  I memorized it in 45 minutes
and I don't think I'm ever going back to QWERTY!




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