Subject: Re: Speeding up netatalk
From: Steven Karel (karelsf@brandeis.edu)
Date: Sat Apr 15 2000 - 17:49:20 EDT
On my intel linux box (350 MHz PII with one UW SCSI disk and one
IDE disk which get about equivalent sustained transfer
speeds...)
[root@squirrel /root]# /sbin/hdparm -tT /dev/sda
/dev/sda:
Timing buffer-cache reads: 64 MB in 0.69 seconds =92.75 MB/sec
Timing buffered disk reads: 32 MB in 2.30 seconds =13.91 MB/sec
[root@squirrel /root]# /sbin/hdparm -tT /dev/hda
/dev/hda:
Timing buffer-cache reads: 64 MB in 0.71 seconds =90.14 MB/sec
Timing buffered disk reads: 32 MB in 2.44 seconds =13.11 MB/sec
transferring to an iMac DV SE over 100 Mbit switched ethernet in my
office:
move a 426 MB file from SCSI disk: 50 sec (8.5 MB/s)
move same 426 MB from IDE disk: 55 sec (7.7 MB/s)
However, moving a typical 633 MB folder containing 4300 files (the hard
drive contents of a "standard" iMac for our lab)...
from the SCSI disk: 9 minutes 11 sec (first 40 sec was just "counting
files") or... 1.3 MB/s
unfortunately, my wife's done in the lab so I have to go home now,
otherwise I'd do the experiment with the IDE disk (I _think_ it'll be
significantly slower due to the slower "seek time".
My point here is that to get the really fast transfer rates...
you don't necessary need a snazzy disk array, but
you DO need to be moving large files.
If you're moving a lot of small files, expect it to be much slower.
steven
On Sat,
15 Apr 2000, John
L Grantham wrote:
> At 13:51 Uhr +1200 15.04.2000, Simon Buchanan wrote:
> >>Just thought it would be fun to compare the two. Of course, the
> >>9500 gets trounced by that monster of yours, but it's not too
> >>shabby... :-)
> >
> >From netfinity 3000 with 128MB and RAID 2x 9.1GB IBM SCSI 3:
> >
> > Timing buffer-cache reads: 128 MB in 1.06 seconds =120.75 MB/sec
> > Timing buffered disk reads: 64 MB in 3.33 seconds =19.22 MB/sec
> >
> >5 x Macs all get 9+MB/sec read and write transfer rate.
> >
> >As Marcus said... it really does come down to motherboard/disk
> >spees, not the proccessor (or thou it helps im sure:)
>
> Yeah, the main brake on my 9500 is undoubtedly the hard drive (narrow
> SCSI). It handles Perl and PHP content very well, actually,
> especially considering the computer's age and type. I could stick a
> Ultra SCSI card in there and pump it up, but somehow the idea of
> doing that to a computer that only sits there for testing my websites
> seems like a waste. ;-)
>
> Of course, once I get that bundle of T1s in my bathroom, maybe I'll
> spring for a UW-SCSI card on the thing. ;-)
>
> I'd be curious to see benchmarks from others with netatalk on other
> older hardware, just for more realistic comparisons...so far y'all
> all seem to have the computer equivalent of monster trucks. I've just
> got an old Pinto. ;-)
>
> Though I like to think of it as a used Jaguar instead.
>
> cya
>
> John
> --
>
> John Grantham | Dipl.-Designer (FH)
> | Homepage http://surf.to/multimedia
> | Linux for Macs: http://www.maclinux.de/
>
Steven Karel, Ph.D.
Biology Department, Brandeis Univ, MS 008
415 South St Waltham MA 02454-9110
TEL 781 736 3104 FAX 781 736 3107
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