I dont have the power of 2 (SMP problem)

MrSlayer · n00b Joined: 17 Aug 2002 Posts: 39

Hi.

I got an nice pair of 1200Mhz Athlon MP in my Asus A7M266-D. But my main problem is that i dont have any luck making my system use both CPU's. I got SMP support in the kernel, i can see both CPU's with cat /proc/cpuinfo and i can see the both in top. I have made MAKEOPTS unmark, and i have tried with different values (3-12). But nomather what i do i cant make the both cpu have a load of atleast 80% each. Either is CPU0 running for full power or else CPU1 is.

BTW i using kernel 2.6.0-test9.

Can anyone help me please?

dizzey · n00b Joined: 03 Oct 2003 Posts: 40

try distributed.net if you dont get full cpu utiliation then something is borked.

otherwise the cpu is seldom the bottleneck so im nut sure if its unormal
top just show snapshots so try distributed and se

nephros · Posted: Wed Nov 26, 2003 4:05 pm Post subject:

Each process can only run at one CPU at a time. If you want things like setiathome (or any other app) to use both processors, you have to start two processes.

Threaded apps like apache and most multimedia encoders/renderers run several threads to take advantage of two processors. For some you will have to tell them explicitly, like bind.
_________________
Please put [SOLVED] in your topic if you are a moron.

ronmon · Posted: Wed Nov 26, 2003 4:44 pm Post subject:

As a long-time SMPer, here's what I've learned. Set your MAKEOPTS at -j3 or -j4. Any more than that won't hurt but it won't help either. I use -j4. When you run 'make' manually, such as when building a kernel, do 'make -j4' to ensure a parallel build if possible. Kernel compiles make full use of the parallel build feature and you should see both cpu's running between 90 and 100% most of the time. This is how I run a kernel build:

MrSlayer · n00b Joined: 17 Aug 2002 Posts: 39

Sorry I forgot som vital information.

It is when i compile i cant get my system to use both CPU's. Everytime i try to emerge something only one thread is startet.

If i run 2 seti clients i can ofcourse get the load of 99,9% on each CPU.

So my problem is that i cant use both CPU's when im emerging something.

BillyBoy · Posted: Thu Nov 27, 2003 12:03 am Post subject:

Where do you make the changes to MAKEOPTS? Is that in make.conf?

ronmon · Posted: Thu Nov 27, 2003 1:17 am Post subject:

Yes, /etc/make.conf. Just uncomment it and set the value.

MrSlayer · n00b Joined: 17 Aug 2002 Posts: 39

I did the "make -j4" for my kernel and instantly (almost then) there was created 4 threads for compiling an both my CPU's where used above 90%, why is it that i just cant make this work on the portage system.

Any ideas?

nephros · Posted: Thu Nov 27, 2003 2:15 pm Post subject:

MrSlayer · n00b Joined: 17 Aug 2002 Posts: 39

I have the makeopts="-j4" in my make.conf and pipe is also in.
I have never ever had this problem before.

ronmon · Posted: Thu Nov 27, 2003 2:18 pm Post subject:

If you have this line set and uncommented in /etc/make conf, most (but _not_ all) apps will build using both cpu's:

MrSlayer · n00b Joined: 17 Aug 2002 Posts: 39

I have it in uppercase.
I am aware that not every thing can use both cpu's. But its only when i make an byhand compile with the -j4 option that i can make the build process use both cpus.

So its unfortunatly not just that simple :cry:

MrSlayer · n00b Joined: 17 Aug 2002 Posts: 39

I can tell why, but its working now. Nothing is changed and it is the same ebuild im compiling.

But atleast its working