[comp.sys.next] 400meg drive in NextStation is fast!

paul@phoenix.Princeton.EDU (Paul Lansky) (02/28/91)

We just got a NextStation with a 400 meg hard drive, and I did 
a quick test of the raw disk speed.  This disk is really hot!

ramirez> temp/ ls -l
total 18616
-rw-r--r--  1 paul     19038208 Feb 27 09:10 piano1.snd
ramirez> temp/ time dd if=piano1.snd of=/dev/null bs=32768
581+0 records in
581+0 records out
0.0u 9.0s 0:17 53% 0+0k 2332+0io 0pf+0w

ramirez> temp/ bc -l
19038208/17
1119894.58823529411764705882

That comes to a transfer rate of over 1.1 meg a second.  This is
*much* faster than the other disks NeXT has been using.
Just thought you'd like to know.

Paul Lansky
Music
Princeton 

paul@princeton.edu

louie@sayshell.umd.edu (Louis A. Mamakos) (03/01/91)

In article <6708@idunno.Princeton.EDU> paul@phoenix.Princeton.EDU (Paul Lansky) writes:
>We just got a NextStation with a 400 meg hard drive, and I did 
>ramirez> temp/ time dd if=piano1.snd of=/dev/null bs=32768
>581+0 records in
>581+0 records out
>0.0u 9.0s 0:17 53% 0+0k 2332+0io 0pf+0w

How much of this file was already lying about in kernel buffers?  I don't 
think that you are only measuring disk performance, but also the effect of
Mach's VM and file mapping.

For those of you running MH:  do a 'scan' of a folder and note how long it
takes.  Do another scan, and notice that it runs MUCH faster than before..

louie