On Wed, 2006-03-01 at 20:49 -0600, Les Mikesell wrote:
On Wed, 2006-03-01 at 19:18, Chris Mason (Lists) wrote:
Sudev Barar wrote:
No load average is not just CPU but reflects all parameters. For pure CPU usage system monitor or similar tool will give better understanding. Also the processes (or dameons) running will really determine the expected load average. But as some else said for genera usage 2~3 times x number of processors is a thumb rule guide. --
I don't think so. I believe, but could be wrong, that load average is the number of processes waiting to execute. Nothing else. However, I reserve the right to be wrong.
It is supposed to be the number of runnable processes (i.e. not waiting on i/o completion) so 1 per processor is busy, higher means something is waiting for CPU. Most programs other than graphics and number-crunching tend to wait more for i/o than CPU, so a load average of 2-3 (x processors) may not reflect noticeable delays.
All of you who have responded have given me good information, and I appreciate it. Altho I don't perceive this machine to *have* a load problem, I was more curious than anything as to what would constitute heavy or moderate loads. This evening, while there were processes active, I did a few tests, one of which was the hdparm -t, and I was quite shocked to see how low the thruput really was, albeit cached. Results were like 18mb/sec where as a few other times during a lighter loading, I/O was what I consider respectable, at 160 +/- mb/ 3 seconds., or approximately 54mb/sec. I also tried a few commands to see what kind of sluggishness was evident, and about the only thing I could really tell a big difference in was deleting messages from evolution, and of all things, logging out. System was *very* slow to log me out, but was about normal when I logged back in. At that time, 7 processes were running, with a load average according to top of 5.4, with 1.4gb memory in use, and 700k of swap, but not actively swapping out. There were a lot of processes that were swapped out, and only a few as runnable. Since the machine only has a single 200gb disk, I suspect part of the sluggishness comes from a bottlenecked disk I/O, just based on so many processes actually in swap.
Again, thanks for everyone's input, and thoughts. I have again, learned a thing or 3!
Regards,
Sam