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ckke

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load average result meaning on command "uptime"

Hi,

   When i issue a command "uptime" in Solaris 7, it got the following output,

 12:28pm  up 82 day(s), 20:07,  16 users,  load average: 0.74, 0.79, 0.81

   I just want to ask for the detail meaning on the load average number values - "0.74, 0.79, 0.81"

   What does they mean? How much is defined to be high cpu utilization?
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yuzh

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yuzh

Use "sar" you can get a more detail output of your system,
do a man sar to find out how to set it up
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ASKER

Then that means in the above example,
there's 0.74 jobs is preforming in last 1 min,
0.79 jobs is performing in last 5 mins.
Am I right?
Moreover, how can i know, or what value will reveal that the CPU is highly utilized?
Yes, that what it means.

To get a better idea about your system, I thing you should use sar instead of uptime.

Just do:
     man sar
     to figure out how, if you have problem whith setting it up, please let me know.


     eg:
     login as root,
     edit your cronatb, add put the following:

   5,35 * * * * /usr/lib/sa/sa1 >/dev/null 2>&1
     
   After a few hour from the first time you put the above entry on the crontab, you can use sar to ckeck out you systems performance.
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ASKER

But i can't find the command sar in my solaris box.
where can i download it?
Running sar is overkill in this situation.

The number of processes in the run queue will almost always be close to one, thats ok.
If however you are starting to see 2-3 processes in queue constantly you have a busy system.
That doesnt mean that something is wrong just that the system is really busy.

commands like "vmstat 5" will give you some info on memory and cpu utilization. Important here is the "sr", that's the scan rate for the pagedaemon.

cpu power is almost never a problem, the problem is mostly processes competing for memory, context switching and maybe interrupts.

You dont say what version of Solaris you are running, the algorithms and memory mgmt has been changed in every release and they will cahange in S9 again.

If you have a pre Solaris 8 system this is useful in the /etc/system file
set priority_pageing=1

This means that processes has priority over mapping files into RAM. This is default from Solaris 8.

But with your numbers, 16 users and < 1 proc in queue you are ok.
Otherwise you will hear about it from the users

Ofcourse you can run sar if you like but its not that trivial AND all tracing consumes even more of system resourses.

hth
"sar" comes with Solaris, it should be:
/usr/sbin/sar

make sure that you have /usr/sbin in your PATH, if you want
to type "sar"
sar is part of the SUNWaccu package. It is on the second Solaris CD.
This means:
If you installed with core or user installationcluster you wont find sar on your system ( or chose to skip install from CD 2 )

installcluster could be found in the file /var/sadm/system/admin/CLUSTER