1. New Member
Join Date
May 2003
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my modem
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## load average with dual core cpu

Hello,
i have a server with this specs:

Pentium4 2.8GHz DC
2048 Mb RAM
250 GB SATA x 2

CentOS as operating system.

What's the problem? I'm running some services that requires load average less than 1.00. Today support told me that 0.00 - 2.00 is a normal load average for a dual processor. I don't agree with this answer.

Thank you.

2. Web Hosting Master
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Jun 2003
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UK
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0-2.00 is reasonable for a Dual Core system ( see http://en.wikipedia.org/wiki/Load_(computing) for more info ) Basically a load of 2.00 means the CPU is 100% busy if everything is CPU bound. I think your software needs to have that limit thing changed though as quite often servers will run above 1.00 even if single cores

3. Web Hosting Master
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Bay Area
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A load of 2 is absolutely fine for a dual core system.
Basically a load of 2.00 means the CPU is 100% busy if everything is CPU bound.
As far as I know the load does not need to be generated by the CPU. You could have a load of 2 due to high IO usage, and still only use 5% CPU

4. Newbie
Join Date
Nov 2006
Posts
10

## Let me explain load averages

The load average is not reliable enough of a metric to judge whether your server is able to do more work than it currently is doing. A dual-proc web server with a load of 4.00 is probably fine. My single-proc web server commonly runs at a load of 8.00 without much loss in responsiveness.

If a dual-proc server has a load of 2.00, it simply means that any new work that comes along (usuaully a new connection from a client machine) won't be processed immediately but will have to wait through the current run queue. If your dual-proc server has a load of 4.00, any new connection is going to have to wait for at least 1 task to complete. I think Linux timeslices are ~10ms, so to estimate the wait time for a new connection, use this formula:

WaitTime = Load / N-proc * 10ms