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2011-12-12, 15:52   #12
Wacky

Jun 2003
The Texas Hill Country

32×112 Posts

Quote:
 Originally Posted by pepi37 Since I have quad, it shows 4 same named processes
It would, perhaps be better if you would actually provide the details of your observations and not just your conclusions. For example, what CPU are you using? Are the hard drives equal in speed and internal caching, how much RAM does the system have, etc.

The base execution times (Windows vs Linux) are similar. I find it suspect that on Windows you find little variance, but significantly more variance on Linux.

This points to some additional process running on Linux. (Hence the previous request for "top" information.)

 2011-12-13, 02:30 #13 Dubslow Basketry That Evening!     "Bunslow the Bold" Jun 2011 40
 2011-12-13, 04:21 #14 axn     Jun 2003 10100000111102 Posts In some linux variants, the default setting is to throttle the CPU down when _only_ low priority processes are running. Could be that. @pepi37: the core part of the computation of PFGW (which is what PRPNet uses, I think), uses the same assembly routines in both Windows and Linux versions. So you're quite wrong in concluding that the problem is with "non-optimized" linux version.
2011-12-13, 04:41   #15
retina
Undefined

"The unspeakable one"
Jun 2006
My evil lair

11000100011112 Posts

Quote:
 Originally Posted by axn @pepi37: the core part of the computation of PFGW (which is what PRPNet uses, I think), uses the same assembly routines in both Windows and Linux versions. So you're quite wrong in concluding that the problem is with "non-optimized" linux version.
Erm, core computations would not be concerned with the OS so I don't think your example says anything. To optimise for an OS would involve setting things like priority and affinity (and lots of other things) to give the core code the best chance to get lots of CPU cycles.

2011-12-13, 07:25   #16
axn

Jun 2003

2×52×103 Posts

Quote:
 Originally Posted by retina Erm, core computations would not be concerned with the OS so I don't think your example says anything.
Ermmm... What example?

2011-12-13, 08:16   #17
retina
Undefined

"The unspeakable one"
Jun 2006
My evil lair

6,287 Posts

Quote:
 Originally Posted by axn Ermmm... What example?
Quote:
 Originally Posted by axn the core part of the computation of PFGW (which is what PRPNet uses, I think), uses the same assembly routines in both Windows and Linux versions.
.

2011-12-13, 08:24   #18
axn

Jun 2003

2×52×103 Posts

Quote:
 Originally Posted by retina .
Ah. Not an example -- I was replying to the topic of discussion. To wit:

Quote:
 Originally Posted by pepi37 I am on PRPNet now. windows ppsLow server WU is finished from 79-80 second less then 1 sec linux - same WU 79-90 second.
I was also trying to disabuse the OP of the notion that there is some kind of anti-linux bias involved.
Quote:
 Originally Posted by pepi37 Problem is always not well optimized application for Linux, and very well optimized app for Windows.

2011-12-14, 09:10   #19
pepi37

Dec 2011
After milion nines:)

1,481 Posts

Quote:
 Originally Posted by Wacky It would, perhaps be better if you would actually provide the details of your observations and not just your conclusions. For example, what CPU are you using? Are the hard drives equal in speed and internal caching, how much RAM does the system have, etc. The base execution times (Windows vs Linux) are similar. I find it suspect that on Windows you find little variance, but significantly more variance on Linux. This points to some additional process running on Linux. (Hence the previous request for "top" information.)
Since there is no GUI on Linux ( I think that will be fastest version) I cannot ( or dont know) how to copy and upload top information on this forum.
Since my kernel is so small, I can assure you that there is no undesirable process. As I say before top shows 99-100 % ( in most cases 100%) using of core per process, so CPU utilization is on maximum.
Last thing: I always used one memory module , and last night I added second one. Computation times are dropped in bot cases ( Windows and Linux) and now is nearly same: difference is less then seconds in Windows or Linux. So it looks like that activating dual channel mode on motherboard solved all problems. And also looks like windows are not so sensitive like like to that option.

2011-12-14, 16:15   #20
Xyzzy

Aug 2002

201678 Posts

Quote:
 Since there is no GUI on Linux ( I think that will be fastest version) I cannot ( or dont know) how to copy and upload top information on this forum.
Code:
\$ top -n 1 > file.txt

2011-12-14, 19:47   #21
chris2be8

Sep 2009

2×32×112 Posts

Quote:
 Originally Posted by pepi37 Since there is no GUI on Linux ( I think that will be fastest version) I cannot ( or dont know) how to copy and upload top information on this forum. Since my kernel is so small, I can assure you that there is no undesirable process. As I say before top shows 99-100 % ( in most cases 100%) using of core per process, so CPU utilization is on maximum. Last thing: I always used one memory module , and last night I added second one. Computation times are dropped in bot cases ( Windows and Linux) and now is nearly same: difference is less then seconds in Windows or Linux. So it looks like that activating dual channel mode on motherboard solved all problems. And also looks like windows are not so sensitive like like to that option.
We still don't have enough information to tell what's going on.
What CPU do you have?
What sort of motherboard is it on?
How big are the memory modules and how fast are they?
What disk(s) do you have?
How much swap space (on LInux type "free -t")?
What version of Windows are you running?
What Linux distribution is it? Post output from "uname -a" and "ls -l /etc/*release".
What program versions are you running? Where did they come from? How do you switch from Windows to Linux (dual boot)?

If you are using a Linux distro that uses more memory than the Windows version it might have been paging before you added memory. That could explain the different speed.

Chris K

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