[syslog-ng] Rpmbuild syslog-ng-3.2.4-1.el6: FAIL: test_nvtable - glib2 hash table

[JP Vossen]

On 07/14/2011 03:16 AM, Balazs Scheidler wrote:
> On Sat, 2011-06-25 at 04:49 -0400, JP Vossen wrote:

>>> On Mon, 2011-06-20 at 20:59 +0100, Jose Pedro Oliveira wrote:
>>>> There is a problem with the hash table implementation of glib2
>>>> version 2.12.3-4 (version that ships in RHEL 5.x).
>>>> More details in:
>>>>    * https://bugzilla.redhat.com/show_bug.cgi?id=714409#c7

[...]

>> Is this hash problem going to cause critical failures?  Under what
>> circumstances?  Or is it, well, it'd be nice if that hash problem didn't
>> happen, but it's not a big deal...
>
> Well, it probably mostly depends on why the hashtable collides in that
> glib version. This hash is a global hash that maps name-value pairs to
> their own unique IDs, which is then used to track name-value pairs in
> log messages.

Sorry if I am being dense.  What name-value pairs used for what?  Would 
this impact a basic syslog-ng config that emulates the sysklogd config? 
  What syslog-ng features need to be in use to trigger this?


> In case the hash table returns non-matching elements, it means that two
> (or more) different name-value pairs will map to the same id,
> effectively one overwriting the other. Whether it happens in practice
> actually depends on what the exact bug in glib is.

Given how old CentOS-5 is, I wonder that this hasn't been noticed and 
reported before now.  Perhaps that means it's rare to hit it in 
practice?  Or maybe just really hard to identify the root cause.

Thanks,
JP
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