[tpop3d-discuss] Memory leak?

Marc Lewis marc at blarg.net
Wed, 8 May 2002 15:57:50 -0700

On Wed, May 08, 2002 at 11:20:07PM +0100, Chris Lightfoot wrote:
> On Wed, May 08, 2002 at 03:04:42PM -0700, Marc Lewis wrote:
> > 
> > Well, its better, but its still leaking a bit:
> > 
> > root     10829  0.0  0.2  5196 2312 pts/1    S    12:18   0:05 /usr/src/tpop3d-1.4.1/tpop3d -f /etc/tpop3d-test.conf -d -v
> > 
> > I have an expect script pounding on it generating about 20-30
> > authentications per minute for the last 30 minutes or so.
> OK. I'll need to look into this one.

I'm happy to run any patches or anything that you like on it.

> > > > I know this is hackish sounding, but what is the motivation for doing all
> > > > of the auth and such before forking?  When I've written simple daemons and
>     [...]
> > That makes perfect sense to me, but since the main server doesn't seem to
> > maintain a persistant connection to the authentication source (at least in
> > LDAP), the overhead of binding to the server per authentication still seems
> > to be there.  Not criticizing, just trying to understand.
> Yeah-- it's not a problem with LDAP. I can't see myself
> rewriting it to be an inetd-style server, though.
> I may add an option to have it restart itself every so
> often.

After looking through the code a bit more, I can see the hesitation in
making this an option.  Would require major reworking.

> > In thinking about this, it is possible that it is a problem in the OpenLDAP
> > libraries.  In my first build of tpop3d, I only configured in Maildir and
> > PAM support.  Since we are using PAM to access LDAP, its possible the leak
> > was caused by PAM's accesses to the LDAP server, since the program never
> > exited, things kept growing, but because of access to libpam.  Building
> > against LDAP directly lessons the leak, but it does definatly appear to
> > still be there.  Others using different non-LDAP authentication methods do
> > not appear to have these leaks.  Hmmm.
> Which version of the OpenLDAP libraries are you using?

v2.0.21-1 from RedHat 7.2 installation, then updates.

Marc Lewis
Network Administrator
Blarg! Online Services, Inc.