Hi,
Has anybody got any advice for the following problem? As I'm seeing some very odd
behaviour with the auditd daemon in RHEL5.2 where under heavy system load the auditd
process doesn't free any resources until all memory is consumed and the kernel kills
the process with an Out Of Memory error.
The system I have is a heavily customised RHEL5.2 with some fairly stringent auditing
rules specified, the config is attached. In addition to these rules there will be various
SELinux AVCs being raised as well as events from my own software so the auditing system is
kept quite busy, see the attached report.txt for the aureport summary .
I can reproduce this behaviour consistently by generating a heavy system load (CPU 100%
usage) while also generating a significant number of audit events. After about 20 minutes
the auditd process will have grown from 8Mb of memory to around 1Gb;
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
3037 root 16 -3 2763m 921m 16 S 3.7 91.2 0:26.49 auditd
If the system is kept busy eventually auditd will consume all the memory available on the
system and the process be killed by the kernel with an Out Of Memory error.
On the face of it this would seem to be a memory leak within auditd however once auditd
has started to consume resources if the system load is reduced and therefore the number
and frequency of audit events is reduced then auditd will free this memory and return back
to the 8Mb memory usage. So it would seem that while auditd is kept busy it keeps hold of
any resources it is allocating. Unfortunately I have systems that run under the level of
load required to cause this issue fairly frequently.
The system is RHEL 5.2 and audit is version audit-1.7.17-3.
Regards
Ross Kirk
Software Engineer
N E X O R
connect transform protect
Tel: +44 (0) 115 952 0500
Fax: +44 (0) 115 952 0519
mailto:ross.kirk@nexor.com <mailto:ross.kirk@nexor.com>
http://www.nexor.com <
http://www.nexor.com>
Nexor is recognised as an Investor in People and is accredited to ISO9001/TickIT and
ISO/IEC27001:2005. Further details of Nexor's accreditations can be found on our
website.
DISCLAIMER: Privileged or confidential information may be contained in this message or
within any files transmitted with it. If you are not the intended recipient, kindly
destroy the message and notify the sender by reply email. Opinions, conclusions and other
information in this message that do not relate to the official business of Nexor are
neither given nor endorsed by it.
Nexor Limited, Bell House, Nottingham Science and Technology Park, University Boulevard,
Nottingham, NG7 2RL
A company registered in England, No: 05152465