[Varnish] #489: Assert error in BAN_CheckObject()

[Varnish]

#489: Assert error in BAN_CheckObject()
---------------------+------------------------------------------------------
 Reporter:  waschtl  |        Type:  defect
   Status:  new      |    Priority:  normal
Milestone:           |   Component:  build 
  Version:  trunk    |    Severity:  major 
 Keywords:           |  
---------------------+------------------------------------------------------
 The following problem has been observed in r3965, as well as r4033:

 Periodically, at irregular intervals, varnish on a production server will
 issue the following error, and restart. As you know, this causes varnish
 to lose the cache, and subsequently the website is not very usable for
 several minutes afterwards.

 {{{
 Apr 15 22:41:49 <hidden-hostname> varnishd[11662]: Child (11663) died
 signal=6
 Apr 15 22:41:49 <hidden-hostname> varnishd[11662]: Child (11663) Panic
 message: Assert error in BAN_CheckObject(), cache_ban.c line 423:
 Condition((o->ban) != NULL) not true.  thread = (cache-worker)sp =
 0x2aaaf504b008 {   fd = 9, id = 9, xid = 1986591368,   client =
 127.0.0.1:44680,   step = STP_LOOKUP,   handling = hash,   ws =
 0x2aaaf504b070 {      id = "sess",     {s,f,r,e} =
 {0x2aaaf504b800,,+297,(nil),+16384},   },     worker = 0x4600a430 {     },
 vcl = {       srcname = {         "input",         "Default",       },
 }, },
 Apr 15 22:41:49 <hidden-hostname> varnishd[11662]: Child cleanup complete
 Apr 15 22:41:49 <hidden-hostname> varnishd[11662]: child (20389) Started
 Apr 15 22:41:49 <hidden-hostname> varnishd[11662]: Child (20389) said
 Closed fds: 4 5 6 9 10 12 13
 Apr 15 22:41:49 <hidden-hostname> varnishd[11662]: Child (20389) said
 Child starts
 Apr 15 22:41:49 <hidden-hostname> varnishd[11662]: Child (20389) said
 managed to mmap 1073741824 bytes of 1073741824
 Apr 15 22:41:49 <hidden-hostname> varnishd[11662]: Child (20389) said
 Ready
 }}}

 This was previously also observed at the following times:

 {{{
 * r3965
 Mar 10 06:21:27
 Mar 18 10:37:45
 Mar 28 07:59:44
 Mar 28 11:52:40
 Mar 30 16:41:45
 Apr  1 11:41:25
 Apr  6 09:47:34
 Apr  6 15:29:26
 Apr  6 21:10:02
 Apr  7 10:50:43
 Apr  7 22:05:46
 Apr  9 06:56:42
 Apr  9 13:16:57
 Apr  9 19:53:26
 * update to r4033
 Apr 15 22:41:49
 }}}

 Varnish is serving a plone website using pound for loadbalancing. The
 website serves up to 80,000 GET-requests per hour.

 Varnish is running on a dual-quad-core machine using Intel E5420
 processors @2.5 GHz with 16 GB RAM, where varnish has a 1 GB cache.

 If you need further specifics to debug the problem, I will gladly provide
 them.

-- 
Ticket URL: <http://varnish.projects.linpro.no/ticket/489>
Varnish <http://varnish.projects.linpro.no/>
The Varnish HTTP Accelerator