What impact if I increase maxfies?

[Takeshi Sugai]

To All.
What impact if I increase maxfies?
For example, to increase 60(defaults) to 4192.

Does it cause to use mroe memory?
I believe that it does not big implact on machine.

I would like to know whatdoes it implact in our machine.
Our env. is HP-UX L-class server, 4GB memory, 11 GB swap

Thank for nay help...

[Stefan Farrelly]

Increasing maxfiles will only use a little more memory by the kernel. You will barely notice the extra memory it will use. With 4GB ram your note going to have a problem.
If you want to measure how much extra memory it will use reboot your server, do a swapinfo -mt command and from the memory line the USED figure is locked memory (used by the kernel and shared mem). Increase maxfiles, reboot, again check swapinfo -mt and you will see how much extra memory the kernel is now using. Should hardly be any.

[Andy Monks]

maxfiles is the per process limit. You can't change it to 4192. The limit is 2048.

However, changing it to 2048 just means processes can if required open 2048 files. You may also need to increase nfile as well if all your processes intent opening 2048 files.

However the effect of increasing maxfiles is fairly small. All it does is use 8 bytes for the pointer and then 56 bytes per file.

[James R. Ferguson]

Hi:

You may want to consider increasing maxfiles_lim along with maxfiles. maxfiles_lim sets the hard limit for the number of files a process is allowed to have open simultaneously. maxfiles is the soft limit and can only be increased by a process up to maxfiles_lim. nfile sets the system-wide ceiling for open files. Thus, we could say that:

maxfiles < maxfiles_lim < nfile

...JRF...

[Nancy Hubert]

If you want to monitor the number of open files there is a public domain
software called

lsof -> list open files

you can download it for free on the web.

http://software.hp.com
click on the "HP-UX public domain software" link.