kernel perameter tuning for HP UX

[Nitesh]

Hi all..

I am reciving slow speed in restoration  from my HP UNIX  IA 64 11.23 media server..

Can any one share information about kernel perameter tuning for HP UX for netbackup 6.5 only

I am working on HP UNIX  IA 64 11.23

Netbackup Plateform : - 6.5

I want to tune kernel parameter for mediaserver ..

Thanks..

[Marianne]

You will find the recommended kernel parameters in the Performance Tuning Guide:

ftp://exftpp.symantec.com/pub/support/products/NetBackup_Enterprise_Server/307083.pdf

As well as LOTS more info....

[Nicolai]

Try to set BPTM restore buffers if not already done so. You configure the BPTM buffers with the commands :

# touch /usr/openv/netbackup/db/config/NUMBER_DATA_BUFFERS_RESTORE

# echo 512 > /usr/openv/netbackup/db/config/NUMBER_DATA_BUFFERS_RESTORE

If you encounter status 89, reduce to 256. No need to restart any daemons.  But I don't think tuning kernel parameters will change the restore speed. Try analyzing the bptm log to see, whether is a tape drive issue or network related.  Info how to analyze the bptm and tuning the BPTM  buffers can be found in the Performance tuning guide.

[Nitesh]

hi,.

If i set this perameter is it increase the restoration speed for my media server..

I dont know how its work .. tell me in breafe..

and how i can use it..

I have HP EML LIBRARY with 12 drives ..

media type hcar and hcart3..

thanks

[Nitesh]

hi all..

following values is alrady set on my server..

NET_BUFFER_SZ  == > 65536

NUMBER_DATA_BUFFERS  ==> 32

SIZE_DATA_BUFFERS  ==>  262144

then which value i can set for NUMBER_DATA_BUFFERS_RESTORE were speed increase in my restoration..

(mediaserver XXXXXX)Storageunit  ==> multiplexing value ==> 32

fragment size ==>  5024

thanks..

[Yasuhisa_Ishika]

As mentioned in Administrator's Guide Volume I or so, multiplexing affect performance on restore.

Try demultiplexing to determine whether MPX makes you restore slow or not, if possible.

NetBackup 7.0 Adminstrator's Guide Volume I, page 572.

About demultiplexing
Demultiplexing speeds up future restores and is useful for creating a copy for
off-site storage. Use the duplication process in the Catalog utility to demultiplex
a backup.
Duplication allows one multiplexed backup at one time to be copied from the
source media to the target media.Whenduplication is complete, the target contains
a single demultiplexed copy of each duplicated backup. (The target can also contain
other backups.) The duplicate copy can be made into the primary copy. Do not
select PreserveMultiplexing in the SetupDuplicationVariables dialog box when
backups are duplicated

[Nicolai]

You can use any value with the power of two (64,128,256,512 etc etc).

But do reduce the MPX value to e.g. 8. A MPX value of 32 is way to high (already suggested in previous post). Set FRAGMENT size to 51200 (50GB). A fragment size to low can have negative impact on performance.

[David_McMullin]

Check out this link!

Please note - we are not using the exact same systems but the effect was immediate and resolved our issues.

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00821409&cc=us&dlc=en&lc=en&jumpid=reg_R1002_US...

vxtunefs -o discovered_direct_iosz=524288 /filesytem

We had a 332GB restore taking over 12hours, after tuning this it completed in less than one.

[Marianne]

David has my vote on this one!