topic Re: How to use ULIMIT Command in Operating System - HP-UX

How to use ULIMIT Command

sysad_boy — Wed, 28 Jan 2009 05:18:36 GMT

Hi guys,

I created a user X for my server but there is a requirement for ulimit values.

How do I edit these ulimit values for a particular user?

Here are the requried values for user X:

1. datasize: 4gb
2. stacksize: 400mb
3. core dump size: 4gb
4. descriptor: 2048
5. memory size: unlimited

Thanks and in advance.

Re: How to use ULIMIT Command

Dennis Handly — Wed, 28 Jan 2009 05:42:52 GMT

1) is controlled by maxdsiz and maxdsiz_64 bit.
2) is controlled by maxssiz and maxssiz_64bit.
4) is controlled by maxfiles and maxfiles_lim.
3) can just be made bigger using ulimit:
ulimit -c $((4194303 * 2))
5) is typically unlimited.

A user will not be able to use 4 Gb for 1) unless he uses 64 bit or jumps through hoops.

If you set maxssiz to 400 Mb, you will take away 400 Mb from maxdsiz for ordinary programs. You can set maxssiz_64bit to 400 Mb without problems.

Re: How to use ULIMIT Command

Steven Schweda — Wed, 28 Jan 2009 05:44:15 GMT

Can you do what you want with one or more
ulimit commands in the user's shell start-up
file (~/.profile, ~/.cshrc, ...)?

Re: How to use ULIMIT Command

sysad_boy — Wed, 28 Jan 2009 05:51:52 GMT

here is my current maxdsiz and maxdsiz_64bit values from kcweb:

maxdsiz 1073741824 1073741824 yes
maxdsiz_64bit 4294967296 4294967296 yes

How is this related to the datasize value that I want which is 4gig?

Re: How to use ULIMIT Command

Dennis Handly — Wed, 28 Jan 2009 06:01:25 GMT

>maxdsiz 1073741824
>maxdsiz_64bit 4294967296
>How is this related to the datasize value that I want which is 4gig?

This says the maximum datasize for a 32 bit app is 1 Gb. For a 64 bit app, it is 4 Gb.

Re: How to use ULIMIT Command

sysad_boy — Wed, 28 Jan 2009 06:25:00 GMT

by the way here is my ulimit -a output from the server:

root:/>ulimit -a
time(seconds) unlimited
file(blocks) unlimited
data(kbytes) 1048576
stack(kbytes) 98252
memory(kbytes) unlimited
coredump(blocks) 4194303
nofiles(descriptors) 2048

Please help me to change the value for "data" to 4194303 instead of the current value 1048576.

Thanks in advance

Re: How to use ULIMIT Command

Dennis Handly — Wed, 28 Jan 2009 12:18:27 GMT

>help me to change the value for "data" to 4194303 instead of the current value 1048576.

As I said, you change maxdsiz to 4294967296. But it will not help you for a 32 bit application. You will have to relink it with -N and use chatr to get more.

If you already have a 64 bit application, you should ignore ulimit.

Re: How to use ULIMIT Command

sysad_boy — Wed, 28 Jan 2009 12:20:13 GMT

Thanks for all the replies.

I was able to modify my ulimit values already.