High runq-sz

[Paul Thomson_2]

Hi

I have a number of rp3410 single CPU machines and they always report a high value in sar for runq-sz.

10:13:00 runq-sz %runocc swpq-sz %swpocc
10:13:02 10.0 100 0.0 0
10:13:04 8.0 100 0.0 0
10:13:06 9.0 100 0.0 0
10:13:08 7.0 100 0.0 0
10:13:10 9.0 100 0.0 0
10:13:12 7.0 100 0.0 0
10:13:14 7.0 100 0.0 0
10:13:16 9.0 100 0.0 0
10:13:18 7.0 100 0.0 0
10:13:20 6.5 100 0.0 0

Average 7.9 100 0.0 0

The CPU shows

10:16:03 %usr %sys %wio %idle
10:16:05 0 0 7 93
10:16:07 1 0 0 99
10:16:09 0 1 4 95
10:16:11 0 0 0 100
10:16:13 0 0 1 99
10:16:15 0 0 1 99
10:16:17 0 0 4 95
10:16:19 0 0 4 96
10:16:21 0 0 1 99
10:16:23 0 0 0 100

Average 0 0 2 98

So there is a little I/O wait, which may explain perhaps the odd process to be waiting. My global priority queue shows

# glance -j2 -iterations 3 -adviser_only -syntax glance.syntax

Welcome to GlancePlus


Global Priority Queue 0.0
Global Priority Queue 0.0
Global Priority Queue 0.0

Up until last weekend, uptime and top showed the load at 5+ constantly. After applying patch PHKL_34310 all was OK.

My question is, why is runq-sz always high ? I have this OS build on 100 or more rp2405 / rp2470s and none of these display this behaviour. runq-sz / global priority and load are all consistent with how busy the systems are.

Thanks
Paul

[RAC_1]

run queue is not important. What you need to look at is priority run queue. So if run queue is high it's not a problem all the time. It is just a average no. of jobs over a period of time.

[Steven E. Protter]

Shalom Paul,

It appears the system is being used. You should have no fear of having to find new work because your system is not being used.

I recommend looking at a broader performance picture:
http://www.hpux.ws/system.perf.sh

I also recommend you take a look from the complaint persepctive. Take basic tuning steps, make sure the kernel is well tuned, the system is well patched and don't worry about numbers on a perfomance chart unless you have response time complaints.

SEP

[Paul Thomson_2]

Hi

How do I check the global priority queue.

Is the value show in glance -B

Under the blocked section ?

Priority 0.0 0.00 0.0

Thanks
Paul

[RAC_1]

You are already doing that.

glance -j2 -iterations 3 -adviser_only -syntax glance.syntax

Welcome to GlancePlus


Global Priority Queue 0.0
Global Priority Queue 0.0
Global Priority Queue 0.0

[Paul Thomson_2]

Thanks,

To be a pain but is the metric I mentioned earlier in glance -B the online way in glance ? The help seems to indicate this....

Thanks
Paul

[RAC_1]

glance -B shows wait states. Different wait states. So I don't think that it shows global priority run queue anywhere.

[Paul Thomson_2]

All, thanks for your posts. It priority run queue from now on !!! :-)

Thanks