dlisoski@pooh.caltech.edu (Derek Lee Lisoski) (03/25/91)
Sorry if this has been covered before...I recently hooked a friends 44MB
Syquest cartridge drive (that he uses on his MAC) to my NeXTStation. The actual
installation was trivial, it took about 5 minutes... it behaves exactly
like a floppy, but it initializes to 38 usable MB. So it seemed like it
would act like a big fast (25ms) floppy, right? Well, it acted like a big
floppy, but it was NOT fast.
I copied an 800k archive file (with 169 files total) onto the drive,
duplicated it and then un-tarred it. The times I got for the duplicate and
the un-tarring, along with those from my 200MB quantum internal HD and a
2.88MB floppy were something like:
Internal HD: Duplicate: 3s (1) Untar: 30s (1)
Syquest: Duplicate: 30s (10) Untar: 6.5 min (13)
Floppy: Duplicate: 1.3min (27) Untar: 5.5min (11)
Although the above times are the averages of several tries, I realize this
is not a very accurate test, but even so...an average factor of about 12
between the Syquest and the harddrive??! Note also, that the floppy beat
the Syquest for untarring.
On the MAC there is less than a 3 to 1 speed advantage for an internal
(fast) harddrive over the Syquest. The MAC floppy is about 1/10 the speed
of the Syquest, while for straight copies it seems slightly faster than
the NeXT floppy.
Question: Is there some fundamentally different way in which the NeXT
treats removable vs. fixed media? The priorities for the different jobs
are the same; but does it cache the internal hardrive and not external
ones? Or is it using the wrong parameters for the Syquest, even though
it seems to recognize the drive?
I could live with having to manually mount and unmount the drive if it
meant a significant speed increase, but I am not sure of how to initialize
the drive as a fixed media device... I can't find a disktab entry for my
internal drive, let alone the Syquest.
I am thinking of buying a Syquest drive, but I would like to know if this
is as fast as it is going to get (I hope not). Any comments or advice
either here or by e-mail would be greatly appreciated...
Thanks
-------------------------------------------------------------------------------
| Derek Lisoski |
| dlisoski@kanga.caltech.edu |
------------------------------------------------------------------------------- ddj@zardoz.club.cc.cmu.edu (Doug DeJulio) (03/26/91)
In article <1991Mar25.025045.29202@nntp-server.caltech.edu> dlisoski@pooh.caltech.edu (Derek Lee Lisoski) writes: > it behaves exactly like a floppy, but it initializes to 38 usable MB. > So it seemed like it would act like a big fast (25ms) floppy, right? > Well, it acted like a big floppy, but it was NOT fast. > Question: Is there some fundamentally different way in which the NeXT >treats removable vs. fixed media? YES! When the NeXT puts a filesystem on a floppy, it optimizes for space insted of speed. I don't know if it does this for flopticals, so it might not be for *all* removable media. You can use tunefs(8) to change this. Type "man 8 tunefs" for more info, or look it up in digital librarian. -- Doug DeJulio ddj@zardoz.club.cc.cmu.edu "You can tune a filesystem, but you can't tune a fish."