System Administration
cancel
Showing results for 
Search instead for 
Did you mean: 

increase ulimit (data) value

SOLVED
Go to solution
Jonathan Caplette_1
Super Advisor

increase ulimit (data) value

Hi guys,

I've a request by Peoplesoft guys working on our servers to increase the data ulimit to higher that 2Gb which is set right now...

# ulimit -a
time(seconds) unlimited
file(blocks) unlimited
data(kbytes) 2097152 <---
stack(kbytes) 131072
memory(kbytes) unlimited
coredump(blocks) 4194303
nofiles(descriptors) 16384

I'm running on Hp-UX 11.11 on a PA-RISC system... I know that's all about maxdsiz and maxsiz_64bit, they are currently set to 2Gb and 4Gb respectively

# kmtune | grep maxd
maxdsiz 0x80000000 - 0X80000000
maxdsiz_64bit 0x100000000 - 0X100000000

How can I increase the maxdsiz to 4Gb? if it is possible...

Regards
Jonathan
11 REPLIES
Steven E. Protter
Exalted Contributor

Re: increase ulimit (data) value

Shalom,

Go ahead and use ulimit to raise the data size to unlimited.

kmtune can be used to increase maxdsiz and maxdsiz_64 or use sam kernel.

kmtune -l will tell you whether these parameters are dynamic or a recompile of the kernel and boot is necessary.

SEP
Steven E Protter
Owner of ISN Corporation
http://isnamerica.com
http://hpuxconsulting.com
Sponsor: http://hpux.ws
Twitter: http://twitter.com/hpuxlinux
Founder http://newdatacloud.com
Bill Hassell
Honored Contributor

Re: increase ulimit (data) value

You can set maxdsiz to 4GB but the Peoplesoft program (if it is old 32 bit code) must be changed to use the 3rd or 4th quadrant. Normally, a 32 bit program only addresses about 960 MB but can be recompiled to handle up to 1.8GB. The chatr program can change the executable, I would want Peoplesoft support to provide the directions as this code is very expensive. A 32bit program can have local memory up to 3.7GB but there are many, many considerations to making this happen.


Bill Hassell, sysadmin
R.K. #
Honored Contributor

Re: increase ulimit (data) value

Hello Jonathan,

As you see that the maxdsiz is 2 Gb and the size of data (ulimit) is also 2 Gb so i believe you need to increase maxdsiz first.

You can have a look on following links, might help you.

http://docs.hp.com/en/1219/tuningwp.html

http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1329920

Regds,
R.K.
Don't fix that what ain't broke
Taifur
Respected Contributor

Re: increase ulimit (data) value

Hi
Check below link for ulimit and kmtune
as follows,

http://docs.hp.com/en/B9106-90008/kmtune.1M.html

http://docs.hp.com/en/B2355-90693/ulimit.2.html

Rgds//
Taifur
Dennis Handly
Acclaimed Contributor

Re: increase ulimit (data) value

>How can I increase the maxdsiz to 4Gb? if it is possible.

You can increase maxdsiz to 4 Gb with kmtune or SAM. This assumes that Peoplesoft has already done the hard work (that Bill mentions) to be able to use this extra space.
Jonathan Caplette_1
Super Advisor

Re: increase ulimit (data) value

Thanks all...

I've another question... you all said that I can increase maxdsiz to 4Gb, but it I look in to SAM -> Kernel -> Config.. the Help on maxdsiz says that the maximum value for maxdsiz is 2GB:

Acceptable Values:
maxdsiz for 32-bit processes:

Minimum: 0x40000
Maximum: 0xfffff000 (64-bit kernel), 0x7b03a000 (32-bit kernel)
Default: 0x10000000

Don Morris_1
Honored Contributor
Solution

Re: increase ulimit (data) value

0xfffff000 is not 2Gb (that's 4Gb minus one page). If you're on a 32-bit kernel, you can't set it higher -- but neither would setting it higher even possibly do anyone any good [since there's no way a user application would get more than 2Gb on a 32-bit kernel].
Jonathan Caplette_1
Super Advisor

Re: increase ulimit (data) value

Thanks Don.. you are so right.. I miss interpreted it...

Thanks everyone.. I'll be changing the value...
Jonathan Caplette_1
Super Advisor

Re: increase ulimit (data) value

closed
Dennis Handly
Acclaimed Contributor

Re: increase ulimit (data) value

>Maximum: 0xfffff000

If you are on 11.23 and using ksh you can use:
$ echo $(( 16#fffff000 ))
4294963200
Bill Hassell
Honored Contributor

Re: increase ulimit (data) value

> Don: [since there's no way a user application would get more than 2Gb on a 32-bit kernel].

Not quite true. Compile a program for EXEC MAGIC and it will be limited to slightly less than 2 GB. But you can use chatr +q3p enable and you can use up to 2.8 GB, and chatr +q4p enable, you'll get 3.7GB or so. The attached c program will demonstrate that capability -- just follow the comments.


Bill Hassell, sysadmin