topic Re: ulimit increase in Operating System - HP-UX

ulimit increase

stevegray — Wed, 06 Jun 2007 04:54:02 GMT

HP-UX 11.31.

I need to increase the value for ulimit from 8192 to 10240.

I believe I need to change maxssize and maxssize_64bit.

Here is what sam says:
Tunable maxssiz
Description Maximum size of the stack segment of a 32-bit process (bytes)
Module vm
Current Value 8388608 [Default]
Value at Next Boot 8388608 [Default]
Value at Last Boot 8388608
Default Value 8388608
Constraints maxssiz >= 262144
maxssiz <= 401604608
Can Change Immediately or at Next Boot

NOTE: If the new Value is specified as Default, the next boot value
will be default value for the tunable as reccomended by HP.
However, if the tunable is being autotuned then the value assigned
will be determined dynamically by kernel during run-time.

New setting[Expression/Value]: ___________________

New setting (evaluated): ___________________
[ Recalculate ]

Do you want to hold the change until next reboot ?: (X) Yes

How do I calculate the values??

Steve

Re: ulimit increase

Matti_Kurkela — Wed, 06 Jun 2007 05:24:04 GMT

"ulimit" contains many limit values. Type "ulimit -a" to see all of them.

Based on the kernel tunable you've identified, you mean "ulimit -s", the stack size limit.

When you use the "ulimit" command, the limit is expressed in kilobytes, while the kernel tunables are expressed in bytes. One kilobyte is 1024 bytes, so the current value in bytes is:

1024 * 8192 = 8388608

which is exactly the kernel tunable's current value.

You'll want to set the tunable to:

1024 * 10240 = 10485760

MK

Re: ulimit increase

stevegray — Wed, 06 Jun 2007 05:26:03 GMT

Thanks.

Steve

Re: ulimit increase

Dennis Handly — Wed, 06 Jun 2007 23:03:04 GMT

Make sure your maxssize_64bit is larger than maxssize.

Also, you might was well make the change immediately, since it is a dynamic tunable.

You can also use kctune to change it.