connection problem with apr_reslist_create and 'min' parameter

["Dr. Peter Poeml" <po...@suse.de>]

Hi,

I am encountering a problem when using apr_memcache, in relation to
apr reslist initialization.

Setup:
- httpd 2.2.6, worker, 32 threads per process
- apr 1.2.11
- apr-util 1.2.10 + apr_memcache from trunk

I was using apr_reslist_create (through apr_memcache_server_create) with
the parameters min 8, softmax 32, hardmax 32.

The issue I'm seeing is that once I stress the server with a bit of
concurrency, the apr_memcache_getp function starts seeing funny
memcached replies, which turn in fact out to be lines it has _sent_ to
the server, as can be demonstrated with fprintf's from inside
apr_memcache (e.g. "VALUE foobar".)

Paul has fixed a resulting segfault in apr_memcache_getp last night,
but the problem as such remained. I can reproduce it well here.

I now found that the problem disappears if I initialize the connection
pool with
min _0_, softmax 32, hardmax 32
instead of min 8. Thus, it seems to me that the problem starts when the
'min' parameter is used.

Could this be a bug in apr_reslist_create? Or some kind of misusage?
I use it in a very similar way as
httpd/trunk/modules/ssl/ssl_scache_memcache.c from httpd trunk.
(Which uses min=0.)

Thanks,
Peter
-- 
"WARNING: This bug is visible to non-employees. Please be respectful!"
 
SUSE LINUX Products GmbH
Research & Development