Linux File Handling Limitations

  • 7019668
  • 08-Jul-2008
  • 07-Aug-2017

Environment

GWAVA 4 (all builds) on Linux

Situation

Informational

Resolution


By default, GWAVA uses 16 threads to scan messages. If for any reason you decide to change this value there is a Linux limitation you should know about.  By default Linux sets a limit on the number of files any process can handle at any given time. It is possible for GWAVA to run into this limit on busy systems, if some changes are not made to the Linux system.

If mail halts and all of GWAVA is still running you may have run into this issue.  To verify that this actually is the problem you are looking at: 

1)  Find the pid of asengine (ps ax | grep asengine).

2)
  Write down the pid.

3)
  Then type lsof -p <asengine_pid>.

4)
  The fourth column over is for FD (file descriptors) and if it shows any of following, then you have run into the limit:

1020r
1021r
1022r
1023r

5)  Use these steps to correct it (for advanced users only):

a)  Set kernel parameter fs.file-max to 65535 by editing the file /etc/sysctl.conf and adding: 

fs.file-max = 65535

b)  Set the hard limit for max number of open files to 65535 by editing the file /etc/security/limits.conf and adding:

* soft nofile 65535
* hard nofile 65535

c)  Edit the file /etc/pam.d/login and add:

session required /lib/security/pam_limits.so
session required /lib/security/pam_unix.so

d)  Set the ulimit for all shells by editing the file:  /etc/profile.local and adding:

ulimit -n 65535

e)  Load the new parameters by typing the following at a terminal prompt:

‘sysctl -p /etc/sysctl.conf’

f)  Restart GWAVA by typing the following at a terminal prompt: 

'rcgwavaman restart'

If you are still experiencing this pausing after making the changes, restart the server.

See also this related article:

Adjusting your GWAVA scan threads (ADVANCED) - https://support.microfocus.com/kb/doc.php?id=7020571

Additional Information

This article was originally published in the GWAVA knowledgebase as article ID 328.