Comment 9 for bug 651428

(In reply to comment #11)
> I think a lot of the RHN code that uses yum APIs is "non-optimal" at
> least, but then it's pretty old.
>
> So I'm not sure which bits you want me to look at in particular.
>
> I don't understand the old code in comment #4, p[0] should traceback with
> KeyError ... no? Looking at getInstalledPackageList closer, this is
> duplicating a bunch of objects in rpmdb, although it is throwing
> the headers away.

Comment #4 is a bit misleading. It shows some changes made in
rhn-client-tools code between RHEL-5.4 and RHEL-5.5, though
I don't believe those changes cause the discussed problem (the
big memory consumption was present also before RHEL-5.4.

> The doTransaction() in that file doesn't look like it is doing much that
> the > yum side wouldn't do. In general I'd expect memory usage to grow in
> runTransaction() because the depsolver runs then, and (although I'm not sure)
> you might be hitting a bunch of caching stuff in yum that doesn't get hit
> before that in your call paths. It's really hard to say if this is "bad"
> or not.
>
> Just looking in that file:
>
> getInstalledPkgObject is slow, I guess you should be calling
> rpmdb.searchNevra(). Certainly never parsePackages.
>
> I'm unsure how runTransaction() can work, it's altering tuples ...
> which should give:
>
> TypeError: 'tuple' object does not support item assignment
>
> ...and add_transaction_data() doesn't do any checking. But neither
> of the last two should cause memory leaks.
>
> What do you do after the transaction runs ... do you del the YumBase
> object (does it all go away, if you do)? We've had a couple of circular
> reference bugs in YumBase, over time.

There's only one yum_base object (instance of YumAction(YumBase) class)
defined at the packages.py module level, no deleting.

Nonetheless, the memory leak (or memory consumption) problem can
be reproduced without involving any RHN code whatsoever.

Install RHEL-5.5 (latest - greatest), setup a yum repo (for example
EPEL-5, no registration to RHN is required) and start yum shell.

In yum shell, install couple of packages, single transaction for every
package:

> install package1
> ts run
...
> install package2
> ts run
...
> etc ...

Never leave yum shell!

Watch the memory of yum process growing every time you execute
the transaction. Sooner or later (depending on how much memory your
system has), ook-killer zooms in and kills your yum.