Toshiba laptop DMA available?

  • Thread starter Thread starter Yousuf Khan
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Yousuf Khan

Hi, I got an old Pentium 3 450MHz laptop, Toshiba Satellite Pro 4200.
It's got an "Intel 82371AB/EB PCI bus master IDE controller". There is a
lot of cpu utilization on this system during disk accesses. Watching
Windows XP's Task Manager, with the kernel statistics turned on, shows
that disk accesses are typically taking up over 80% the CPU, and 90% of
that is inside the kernel, indicating a lot of PIO activity. It's using
the standard Microsoft drivers, and they show that they're set to use
"DMA if available". I don't think they are using DMA. Is there any way
to see if the drivers are actually using DMA mode? Also would an upgrade
to Intel drivers help anymore? There was a time when going to the Intel
drivers reduced cpu utilization tremendously in the Windows 95/98 days,
don't know if it's still the case in XP.

Yousuf Khan
 
Windows XP's Task Manager, with the kernel statistics turned on, shows
that disk accesses are typically taking up over 80% the CPU, and 90% of
that is inside the kernel, indicating a lot of PIO activity. It's using
the standard Microsoft drivers, and they show that they're set to use
"DMA if available". I don't think they are using DMA. Is there any way
to see if the drivers are actually using DMA mode?
Click to expand...

Yes. Read the next line in "Advanced Settings"; "Current Transfer Mode:".
Does it show "Ultra DMA Mode x"? Where x is between 2 and 6?
 
Peter said:
Yes. Read the next line in "Advanced Settings"; "Current Transfer Mode:".
Does it show "Ultra DMA Mode x"? Where x is between 2 and 6?
Click to expand...

Oh, you're right, I totally missed that when I went through it the first
time.

Okay, they are both showing Ultra DMA mode 2. So I guess the next
question is if they're using DMA, then why is there so much CPU overhead?

Yousuf Khan
 
Yousuf Khan said:
Hi, I got an old Pentium 3 450MHz laptop, Toshiba Satellite Pro 4200.
It's got an "Intel 82371AB/EB PCI bus master IDE controller". There
is a lot of cpu utilization on this system during disk accesses.
Watching Windows XP's Task Manager, with the kernel statistics turned
on, shows that disk accesses are typically taking up over 80% the
CPU, and 90% of that is inside the kernel, indicating a lot of PIO
activity. It's using the standard Microsoft drivers, and they show
that they're set to use "DMA if available". I don't think they are
using DMA. Is there any way to see if the drivers are actually using
DMA mode?
Click to expand...

You've already had this answered.
Also would an upgrade to Intel drivers help anymore? There was a time
when going to the Intel drivers reduced cpu utilization tremendously in
the Windows 95/98 days, don't know if it's still the case in XP.
Click to expand...

Yes it is, well worth trying.

Definitely get a better result in HDTach under XP
with the intel chipset controllers I have tried it with.
 
Oh, you're right, I totally missed that when I went through it the first
time.
Click to expand...
Okay, they are both showing Ultra DMA mode 2. So I guess the next
question is if they're using DMA, then why is there so much CPU overhead?
Click to expand...

It may just be that your CPU needs this much effort for moving the
data within main memory. If it is a fast (new) disk, I guess this could
be the issue.

Arno
 
Arno said:
It may just be that your CPU needs this much effort for moving the
data within main memory. If it is a fast (new) disk, I guess this could
be the issue.
Click to expand...

Actually, I did upgrade the disk drive to a 40GB Seagate about a year
back. Replaced the original 10GB IBM disk that it came with.

Yousuf Khan
 
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