Messages in this thread |  | | Date | Tue, 4 May 1999 04:51:57 -0400 (EDT) | | From | "Mike A. Harris" <> | | Subject | RE: Kenwood/Hi-Val True-X 40x CDROM drive. |
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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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