On Mon, 14 Aug 2000, Vojtech Pavlik wrote:
<snip my stuff>
> It definitely runs at UDMA66 speed. It's quite likely that the harddrive
> can't deliver more than 14 megs per second. I have a IBM-DPTA-372050,
> which is about the same, but 7200 rpm. It does 20 megs per second. If
> you recompute that to 5400, which is your drive, you get the speed you
> get. It doesn't help if you run the interface faster here.
I hope this isn't true. :(
IBM says the drive does 15.5-18.7 MB/s.
http://www.storage.ibm.com/hardsoft/diskdrdl/desk/ds25gp.htm
IBM also says that a similar drive that only does ata33 has a sustained
throughput rate of 12-16 MB/s.
http://www.storage.ibm.com/hardsoft/diskdrdl/desk/ds16gp.htm
My hdparm results (14.8 MB/s) are right in the middle of the ata33 range,
and remain exactly the same when switched to ata66.
I also found a post from Andre refering to these drives as being crippled
to ata33 but fixable. :)
here is that post.
http://x56.deja.com/[ST_rn=ps]/getdoc.xp?AN=570509454&search=thread&CONTEXT
=966297159.1263337479&HIT_CONTEXT=966297081.1262616587&HIT_NUM=10&hitnum=0
>
> Why the UDMA66 speed isn't autoselected is beyond me, though.
It a sign that things aren't quite right :o)
I know this is a performance thing and you guys must be busy, so if you
want to back burner this issue until later (after 2.4 maybe) thats cool.
But, I really don't believe I am getting my money's worth from these new
drives that I bought specifically for there ata66 capabilities. Are there
any other tools or utils I could use to confirm I am maxing out the
drives?
Thanks for your time,
Shane
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This archive was generated by hypermail 2b29 : Tue Aug 15 2000 - 21:00:35 EST