From: bill@yossarian.ucsd.edu (Bill Reynolds) Subject: Re: SCSI Performance (Yet Again) Date: 23 Aug 1993 21:01:24
In article <u5oq9B1w165w@xivic.bo.open.de> ws@xivic.bo.open.de (Wolfgang Schelongowski) writes:
How about
date;dd if=/dev/sda of=/dev/null bs=131072 count=512;date
(This does only a read, you have to save and restore via dd
if you want to test write. Just be _very_ careful about _where_
you test ! Maybe you should backup the disk.)
That took 69 seconds => 950 KByte/sec for raw I/O. Under BSDI,
the numbers are 36 seconds on /dev/rsd0a => 1820 KByte/sec.
Hmm.. I don't know what my problem is. 486/66 clone AHA1742, 1G
Fujitsu disk, in extended mode with 32M of main memory on an EISA bus,
I get 261s for the above command => 257 KByte/sec.
I'm running Linux yossarian 0.99.11 #3 Tue Jul 6 18:58:52 MDT 1993 i486
(Wait a sec, as your humble narrator tries some stuff).
Ok, the above was done with X and term running (interrupts up the
wazoo!). Killing all extraneous processes, I get 61s => 1100 Kb/sec -
much better! So it's obvious that these benchmarks depend on a lot
more than just disk/bus speed.