topic Re: Need help with memory management in Operating System - HP-UX

Need help with memory management

Paker Olga — Wed, 05 Feb 2003 12:09:44 GMT

Hello,

We need to increase the data segment available for our process to 2.8 Gb, as "chatr +q4p enable" allows (or at least +q3).
Now we are using EXEC_MAGIC option, but we are already close to the limit.
Could anyone help me with more information on q3 and q4? How exactly the memory is managed? What happens with the shared objects? What are the negative sides of those options?

Thanks and Regards,
Olga.

Re: Need help with memory management

John Palmer — Wed, 05 Feb 2003 12:21:27 GMT

Have you read the Process Management White Paper, supplied with HP-UX?

It's: /usr/share/doc/proc_mgt.txt

Regards,
John

Re: Need help with memory management

T G Manikandan — Wed, 05 Feb 2003 12:26:37 GMT

The link John has pointed out is for process Mgt.There is also another white paper for memory mgt.

/usr/share/doc/mem_mgt.txt

Re: Need help with memory management

Bill Hassell — Wed, 05 Feb 2003 12:34:04 GMT

Always check both of the papers mentioned above, and make sure that you are up to date on patches. Getting the upper quadrants to map into a single data area is tricky and needs the latest memory management patches. Note that *ALL* problems with quadrant mapping limitations disappear if you simply recompile your program as a 64bit executable. Now you can have hundreds of Gb for a data area. (assuming you have a 64bit OS and CPU).