How to check per process and system file descriptor limit?

[Jarod Wang]

Hi Experts,

Could you please tell me how to check:

1. Per process file descriptor limit?

2. System file descriptor limit?

3. How to increase these two limits?

I'm using HP-UX IA64 B.11.23.

Thanks in advance.

[Dennis Handly]

>1. Per process file descriptor limit?

There are two: maxfiles(5) and maxfiles_lim(5)
ulimit -a will show the former.

>2. System file descriptor limit?

nfiles(5)

>3. How to increase these two limits?

You can list or increase the 3 limits with kctune(1m).

[Deepak Kr · Accepted solution]

Hi,

See this:
#kctune -v maxfiles
Tunable maxfiles
Description Initial (soft) maximum number of file descriptors per process
Module fs
Current Value 10000
Value at Next Boot 10000
Value at Last Boot 10000
Default Value 2048 (automatic)
Constraints maxfiles >= 32
maxfiles <= 1048576
maxfiles <= maxfiles_lim
Can Change At Next Boot Only

#kctune -v nfile
Tunable nfile
Description Maximum number of file descriptors (system-wide)
Module fs
Current Value 194348
Value at Next Boot 194348
Value at Last Boot 194348
Default Value 65536 (automatic)
Constraints nfile >= 2048
nfile <= 2147483647
nfile >= (2 * maxfiles_lim)
Can Change Immediately (Automatic Tuning Disabled)

To change e.g.

To increase a tunable's value by 100:

# kctune tunable_name+=100