general/4463: some httpd have extremely large memory footprints, 10x the norm

[George Michaelson <gg...@dstc.edu.au>]

>Number:         4463
>Category:       general
>Synopsis:       some httpd have extremely large memory footprints, 10x the norm
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    apache
>State:          open
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Sun May 23 19:10:02 PDT 1999
>Last-Modified:
>Originator:     ggm@dstc.edu.au
>Organization:
apache
>Release:        1.3.4
>Environment:
Solaris 2.6, gcc 2.8.1
SunOS mirror.aarnet.edu.au 5.6 Generic_105181-13 sun4d sparc SUNW,SPARCserver-1000

>Description:
the host in question is a large FTP/www mirror and provides access to
files such as RedHat ISO images, StarOffice as http protocol downloads as
well as FTP.

we see random (unknown) instances of httpd where the memory footprint grows
to be 20-30Mb, with 10+ Resident. kill -HUP clears.

After kill -HUP the machine stops swapping. /tmp is in swap, we then also
see an end to "out of /tmp" space problems.

top and vmstat and ps agree about the process size
>How-To-Repeat:

>Fix:
Without having looked in any depth, I wonder if use of a mmap() form of I/O
is leading to large objects getting mapped into the server memory space and
then not getting released.

setting the number of calls before child-death down reduces the problem so
we have a workaround.

I did search manual pages but found no reference to directives which seem to
address potential memory growth issues.

cheers
	-George
>Audit-Trail:
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