HPUX 11.31 memory utilization

[Camel_1]

Hi there,

I have a VM guest running HPUX 11.31, install from DVD and take all kernel parameter as default. The VM has 32GB allocated, however, when bring up the OS, the memory utilization is showing 30% already (which is about 10GB), there was no application/database running, just only OS, I am wondering what kernel parameters I have to look into to reduce the memory utilization.

Thanks,

Simon

[Tingli]

How about dbc_max_pct? Down to 10 from 50.

[Vinod Kumar Yadav]

Hi,

How many HP-UX IVM VMGUEST are running on the VMHOST,what is the percent of Memory present on the VMGUEST.


10% of the Total Memory is to be used by VMHOSTS.

Just give this command then you got the output of RAM & CPU Utilization.

# hpvmstatus -P vm00 (Example â VMGUEST name)

[Virtual Machine Details]
Virtual Machine Name VM # OS Type State
==================== ===== ======= =======================
Eccr3qa 2 HPUX On (OS)

[Authorized Administrators]
Oper Groups:
Admin Groups:
Oper Users:
Admin Users:
[Virtual CPU Details]
#vCPUs Entitlement Maximum
====== =========== ======================================
1 50.0% 100.0%

[Memory Details]
Total Reserved
Memory Memory
======= ========
9 GB 64 MB

[Storage Interface Details]
Guest Physical
Device Adaptor Bus Dev Ftn Tgt Lun Storage Device
======= ========== === === === === === ========= ===========
Disk scsi 0 1 0 0 0 lv /dev/vg02/rlvol1
Disk scsi 0 1 0 1 0 lv /dev/vg04/rlvol1
Disk scsi 0 1 0 2 0 disk /dev/rdsk/c6t1d2
Tape scsi 0 1 0 6 0 attach /dev/rscsi/c5t0d2

[Network Interface Details]
Interface Adaptor Name/Num PortNum Bus Dev Ftn Mac Address
========= ========== ========== ======= === === === ========
vswitch lan QASW 1 0 0 0 96-84-54-92-41-31

[Misc Interface Details]
Guest Physical
Device Adaptor Bus Dev Ftn Tgt Lun Storage Device
======= ========== === === === === === ========= ============
Serial com1 tty console



Thanks

[Roopesh Francis_1]

please check this link:
http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1337384

[Steven E. Protter · Accepted solution]

Shalom Simon,

1) Collect some data on actual use.
http://www.hpux.ws/?p=8

2) Maybe some performance info
http://www.hpux.ws/?p=6

Item one will show you what processes are using how much memory.

kctune -l
Lets see what your kernel parameters are.

I don't find this use out of range, especially if this is a default install and dbc_max_pct buffer pool is set to 50%

That is a big eater of memory right there.

SEP

[Patrick Wallek]

dbc_*_pct parameters do not exist with HP-UX 11.31.

The new parameters are filecache_min and filecache_max. However, the default values are still the same. You could try tuning filecache_max, which is a DYNAMIC parameter now.

[Andrey Chipalyuk]

The limits of the file system Buffer Cacheâ which is still being used for file system metadataâ are automatically set to certain percentages of filecache_min and filecache_max. Therefore, the dbc_min_pct and dbc_max_pct tunables, as well as the bufcache_max_pct, bufpages, and nbuf tunables are obsolete in HP-UX 11i v3 and have been removed.

See:
http://h71028.www7.hp.com/ERC/downloads/4AA0-7157ENW.pdf

[Venkatesh BL]

How did you measure the memory utilization? Can you post the output?

Please post the current value of 'filecache_min' kernel tunable as well.

[Camel_1]

Hi all,

The server is running HPUX 11.31 on a VM guest. Pls see the attached output file, the filescache kernel values listed in the following.

filecache_max 32679649280 Default Auto
filecache_min 3267964928 Default Auto

Correction the VM has 64GB instead of 32GB, but still the memory utilization is still high (10GB), cause the application people question they will only has 54GB to use.

Thanks all,

Simon

[Don Morris_1]

Well, 15% is a lot different from 30%.

First -- v3 is going to use absolutely guaranteed 5%. In practice, it will eat around 8 to 9%. So you're using an additional 6%, which considering you told the filecache it can go between 5 to 50% (defaults) may not be that surprising.

kcusage filecache_max?

And remind the application folks that an idling OS will cache things more than a loaded OS. (And that bringing up a workload may entail new kernel metadata that isn't reflected here yet). You can't know exactly how much they'll have based on a simple idle state. Once free memory starts to get low - the OS will push caches down. [But your current settings mean that at least 10% is going to be held by the OS (5% for per-page metadata, 5% for filecache_min), more likely at least 14 to 15%, so this isn't a bad ballpark to start from.]

[Camel_1]

Thanks,

base of the following, if reduce the filecache_max does it help to reduce the utilization also?

Tunable Usage / Setting
=============================================
filecache_max 211832832 / 32679649280

[Patrick Wallek]

Resetting filecache_max probably won't affect your system as it is now.

The usage is currently only 202 MB out of 30 GB.

Tunable Usage / Setting
=============================================
filecache_max 211832832 / 32679649280

211,832,832 bytes = 202 MB

32,679,649,280 bytes = 30.4 GB