topic Re: Decreasing the Load in Operating System - HP-UX

Decreasing the Load

prasadb — Thu, 03 Apr 2008 14:27:26 GMT

my one of the server is showing load between 7-8 by top command. please let me how can i reduce it ?

Re: Decreasing the Load

HGN — Thu, 03 Apr 2008 14:38:45 GMT

Hi

From top you can determine what is taking up the load on the CPU's then you can determine if anyone of them can be terminated. Load of 7-8 cannot be bad unless you see performance issues.

You can browse/search the itrc forum site for any thread for cpu load, I have one below

http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1074698

Rgds

HGN

Re: Decreasing the Load

prasadb — Thu, 03 Apr 2008 15:04:47 GMT

Thanks HGN.

i would like to know how much load can a HP UX server could have without degrading the performance..

Thanx in advance

Re: Decreasing the Load

Andres_13 — Thu, 03 Apr 2008 15:49:51 GMT

That is a very difficult question to answer to because there are a big number of vars that can affect performance.

Not sure if there is a limit but in my prod servers i have rates between 1.7 - 1.8.

Regards!

Re: Decreasing the Load

Bill Hassell — Thu, 03 Apr 2008 22:18:26 GMT

The "load" reported by uptime or top is very, very misleading. It represents the number of processes running or ready-to-run during the measurement period. There is no correct load and the actual number is meaningless unless you also state the number of processors in your computer. A load of 7-8 is nothing for a 32 processor computer. On the other hand, 7-8 on a 1-processor system needs to be investigated. Note that I did not say it was bad, just needs to be understood.

First, the world's smallest compute-intensive script:

while :
do
:
done

Now run this and you will consume 100% CPU while it runs (forever until you kill it). Run 10 copies of this script and your load will be 10, even if you only have 1 processor. The amazing part is that with a load of 10 from this script, everyone can edit their files and login, etc with no visible effect on interactive performance. That's the beauty of timeslicing and priority handling. These compute-intensive processes drop to the bottom of the priority chain to allow I/O and other processes to continue.

The load is unimportant unless users are complaining -- but that assumes that things were much faster before the load increased. The two ways to reduce the load is to increase the number of CPUs in your computer, or terminate processes that consume a lot of CPU time (I do NOT recommend the second choice as you will break things...)