topic Re: Performance issue in Operating System - HP-UX

Performance issue

Helen French — Thu, 10 Jan 2002 15:29:17 GMT

Hi,

I have 3 old HP servers in a site (2* K210 and G40). All the three servers are running the same applications (Oracle + Java + Sapphire + Netscape /iplanet ). The G40 is running with 11.0 (32bit) and two K210 are running with 10.20.
Now, when the development team tests an application upgrade on each server, the G40 works fine while the two K210 are running very slow. Both K210 are running with 2 processors (G40 with single CPU) and with more memory/swap than G40. The only difference is in the OS.

Here, does an OS upgrade to 11.0 (32bit) on the K class servers will make any difference ?

Does a kernel tuning will help me ?

what are the other things which I need to look in to ?

Thanks in advance for all your response !

Shiju

Re: Performance issue

James R. Ferguson — Thu, 10 Jan 2002 15:41:00 GMT

Hi:

As a first approximation, I'd compare the kernel parameters of the two servers. I'd use SAM to view them since you don't have 'kmtune' at 10.20, and 'sysdef' may have some anomolies at 11.x

Regards!

...JRF...

Re: Performance issue

Tim D Fulford — Thu, 10 Jan 2002 15:51:27 GMT

shiju

My gut instinct is that you have a memory bottle neck on the K's (as you said the G has more memory). However, this is rushing to a conclusion.

1 - get some statistics from sar, top etc or my favorite MeasureWare for all of the boxes.
so you could use the following to get disk & cpu utilisation for 20 seconds:
sar -du 20 1
virtual memory statistics:
vmstat
2 - I would start simple & check CPU usage, disk activity, swap etc then home in on the differences from there
3 - I would look at the difference between the kernel setings too, though 10.20 is different to 11.00 for some things.
4 - Are there any other H/W differences disk subsystem, network & so forth? Do you use the same type of filesystem Vxfs, HFS....

Without more info it would be difficult to point a specific problem.

Tim

Re: Performance issue

Helen French — Thu, 10 Jan 2002 15:57:21 GMT

Exactly JRF,

that was my first step. I got it from SAM on all the three systems and now comparing those. Do I need to be more concerned about some specific parameters ? I think there will be some differences, the way 11.0 and 10.20 handles the kernel parameters (?)

Can I observe the kernel parameters overflow through Glance ? ( like sar -v)

Shiju

Re: Performance issue

Helen French — Thu, 10 Jan 2002 16:17:17 GMT

Hi Tim,

1) You read it wrong. G40 has less memory. Both K210 has more memory and swap than G40.

2)There are H/W differences between systems. G40 uses all SE SCSI disks, where as K210 uses Model 20 diskarray and HASS boxes. So again, it should run faster.
3) The network speed remains the same.
4) G40 uses all vxfs file systems except /stand. K210 uses hfs mostly except some file systems with vxfs.

Shiju

Re: Performance issue

Tim D Fulford — Thu, 10 Jan 2002 16:30:13 GMT

I realy must learn to read!

o HFS filesystems have variable (at set up time) block sizes. VxFS has 1kB fragment & 8kB block. If HFS filesystems are used for Oracle, do they have equivalent sizes?

o Do you have any performance statistics, sar, top, MeasureWare etc?

Tim

Re: Performance issue

Helen French — Thu, 10 Jan 2002 16:43:45 GMT

Tim,

Yes I did check the performance through sar, top and glance. The user load is high in K210 when they test the software.

Shiju

Re: Performance issue

Tim D Fulford — Thu, 10 Jan 2002 16:55:39 GMT

can you attach

sar -du 20 1

or a top output etc?

Tim

Re: Performance issue

James R. Ferguson — Thu, 10 Jan 2002 16:58:51 GMT

Hi Shiju:

There is one favorite kernel parameter that a few of us have had experience with -- 'timeslice'. The usual database templates set this to <1> instead of the default <10>. Since this parameter controls the frequency of process context switching, setting it too low (genearlly less than 10) leads to doing process switching at the expense of real work.

Regards!

...JRF...

Re: Performance issue

Helen French — Thu, 10 Jan 2002 17:10:31 GMT

Hi,

Tim - I will post the outputs shortly. I have to wait for the development team for testing their jobs again.

JRF - I checked the 'timeslice' parameter and it is '10 ' in all servers.

Any more inputs ?

Does anybody has any more suggestions or answers ?

Re: Performance issue

Mike Barron_3 — Thu, 10 Jan 2002 18:41:43 GMT

A couple things....

If the user % in CPU utilization is high and sys % and idle % is low, that is good. That means the application that the developers are running is using most of the CPU activity.

You said the G class has less memory, but did ya check your dbc_max kernel setting? default it is set to use 50% of your physical memory. We had a major memory bottleneck here and found out we should change that kernel setting to use 10%. It helped tremendously.

1 more thing just to add, check your disk utilization. Are you getting and disk bottlenecks?

Re: Performance issue

Helen French — Thu, 10 Jan 2002 18:51:05 GMT

Hi Mike,

Thanks for the reply. I have %idle also high, but %sys comparatively low.

Tha dbc_max is default now in all servers, but i will change this as part of the Kernel tuning.

I will assign you points once I finished these tasks.

Thanks!
Shiju

Re: Performance issue

Sanjay_6 — Thu, 10 Jan 2002 18:59:03 GMT

Hi Shiju,

Take a look at the hp-ux performance and tuning guide,

http://docs.hp.com/hpux/onlinedocs/os/11.0/tuningwp.html

Hope this helps.

Regds

Re: Performance issue

Helen French — Thu, 10 Jan 2002 19:03:48 GMT

Thanks Sanjay, ..that's an excellent guide !

Shiju

Re: Performance issue

Sridhar Bhaskarla — Thu, 10 Jan 2002 19:48:19 GMT

Hi Shiju,

How about doing some kind of benchmarking on G40 and K Servers?. For ex., copy a 20 MB file from one file system to other and compare the difference. Make a C program that computes prime numbers, run it on both the systems and see the difference. Try ftping some stuff from the same source etc.,

I would certainly check to see if 11.0 helps. Borrow sometime from your development team. Make couple of make_recovery tapes on K server.If possible add an additional disk to K server and install 11.0 32bit on it. Import the file systems and ask your developers to run the application and see how it works. If not, you can always revert back to 10.20 either through make_recovery tape or the old boot disks.

-Sri

Re: Performance issue

Helen French — Thu, 10 Jan 2002 19:51:19 GMT

Hi Sri,

I will defenitely check the options given by you and will assign points after that.

The 11.0 upgrade is my last option.

thanks for the rpely!
Shiju

Re: Performance issue

Helen French — Thu, 10 Jan 2002 22:05:25 GMT

Hi Sri,

I did try the options u have listed and seems like the K-class server works fine than G.

I could see some difference in the kernel parameters and will try changing that, once i will be able to take a shutdown of the server.

Does anybody has any other suggestions / experiences ?

Shiju

Re: Performance issue

Sanjay_6 — Thu, 10 Jan 2002 22:11:02 GMT

Hi Shiju,

Here are two links which might be useful,

http://us-support.external.hp.com/cki/bin/doc.pl/sid=c70ed41c0e60c4e701/screen=ckiSearchResults?mode=id&searchString=KNC061098001

http://us-support.external.hp.com/cki/bin/doc.pl/sid=c70ed41c0e60c4e701/screen=ckiSearchResults?mode=id&searchString=A4460661

Hope this helps.

Regds

Re: Performance issue

Tim D Fulford — Fri, 11 Jan 2002 10:18:44 GMT

Hi again

There is also a doc that I found useful which is S Ciullo & D. Grumann's "HP-UX Performance CookBook" he uses MeasureWare & Glance or GlancePlus which needs to be purchased if you do not already have it.

http://h21007.www2.hp.com/dspp/files/unprotected/devresource/Docs/TechPapers/UXPerfCookBook.pdf

Tim

Re: Performance issue

Ruediger Noack — Fri, 11 Jan 2002 10:33:40 GMT

Hi,

have a look to %wio with sar -u.

Ruediger