On 23.10.2014 13:25, Etienne Champetier wrote:
After some more investigation, reading many lines of code with a collegue,
we came to the conclusion that this exception is impossible :)
(yet the web is stuck on it)
Are you sure that this NameObjectCollection isn't mistakenly accessed
from multiple threads?
Look System.Web.Configuration.WebConfigurationManager.GetSection
all the way up the stacktrace. There are several scary parts that
deal with locking.
Robert
m_ItemsContainer is an hashtable, and a private field of
NameObjectCollectionBase
class (new HashTable(0,StringComparer.Ordinal)).
The exception tell us that there is already a key 'httpModules' in
m_ItemsContainer.
Reading the code the only way we go from BaseSet to BaseAdd is if
FindFirstMatchedItem('httpModules'), so if (_Item)m_ItemsContainer[
'httpModules'] is null,
so if the value is null (the key exists, we got an exception to prove it :))
if i'm right, we are sure that we have ('httpModules',null) in
m_ItemsContainer.
Now m_ItemsContainer only modifications are:
0) m_ItemsContainer = new Hashtable (m_defCapacity, equality_comparer);
1) m_ItemsContainer.Clear ();
2) _Item newitem=new _Item(name, value);
m_ItemsContainer.Add(name,newitem);
3) m_ItemsContainer.Remove(name);
So there is no way there is ('httpModules',null) in m_ItemsContainer
Please someone tell me where i'm wrong
https://github.com/mono/mono/blob/master/mcs/class/System/System.Collections.Specialized/NameObjectCollectionBase.cs
Thanks
Etienne
2014-10-21 14:54 GMT+02:00 Etienne Champetier <champetier.etie...@gmail.com>
:
Hi,
At my firm we are running multiple webapplication using mono (nginx +
fastcgi-mono-server2.exe) on a cluster of 4 VM, 2 vcpus.
One of them is restarted every day at 1h45 (small memory leak).
3 weeks ago we went from 8VM with 1vcpu (no restart problem) to 4VM with
2vcpus, and now,
it's the 3rd time in 2 weeks that on one VM, the restart doesn't work well
and we have:
[System.ArgumentException]: Key duplication when adding: httpModules
at System.Collections.Hashtable.PutImpl (System.Object key,
System.Object value, Boolean overwrite) [0x00000] in <filename unknown>:0
at System.Collections.Hashtable.Add (System.Object key, System.Object
value) [0x00000] in <filename unknown>:0
at System.Collections.Specialized.NameObjectCollectionBase.BaseAdd
(System.String name, System.Object value) [0x00000] in <filename unknown>:0
at System.Collections.Specialized.NameObjectCollectionBase.BaseSet
(System.String name, System.Object value) [0x00000] in <filename unknown>:0
at System.Configuration.ConfigurationSectionCollection.get_Item
(System.String name) [0x00000] in <filename unknown>:0
at System.Configuration.Configuration.GetSection (System.String path)
[0x00000] in <filename unknown>:0
at System.Web.Configuration.WebConfigurationManager.GetSection
(System.String sectionName, System.String path, System.Web.HttpContext
context) [0x00000] in <filename unknown>:0
at System.Web.Configuration.WebConfigurationManager.GetSection
(System.String sectionName, System.String path) [0x00000] in <filename
unknown>:0
at
System.Web.Configuration.WebConfigurationManager.GetWebApplicationSection
(System.String sectionName) [0x00000] in <filename unknown>:0
at System.Web.HttpApplication.InitOnce (Boolean full_init) [0x00000] in
<filename unknown>:0
The really cool stuff is that even if it's a 500 error, the returned http
code is 200 :)
I've already checked and all files are equal (dll, exe, conf), all VM conf
are equal (vcpu, memory, ...), ...
I'm not able to reproduce the bug (restart under high load (ab -c 50 -n
100000)) so can't tell if the bug is there in the newest version.
We are using a version of mono before 3.2.7
(92887027be801b012846866208e6b4e362a4fc24) and fastcgi-mono-server2 (xsp)
version 2.10.2-1 (old version build on 14/09/12 by someone at my firm)
I know we are using old version but it seems that the bug is still there:
https://bugzilla.xamarin.com/show_bug.cgi?id=18303
I've run lsof on the processes (the stuck one and one working), and by
comparing the 2, i see that App_global.asax_XXXXXXX.dll
is here in both case, but not App_Web_XXXXXXXX.dll (only on the working
one) (see attachment)
I have root access on the VM with the stuck process, and i'm on irc right
now (champtar), so if you have some ideas to gather more info to kill this
bug
Thanks in advance
Etienne
_______________________________________________
Mono-devel-list mailing list
Mono-devel-list@lists.ximian.com
http://lists.ximian.com/mailman/listinfo/mono-devel-list
_______________________________________________
Mono-devel-list mailing list
Mono-devel-list@lists.ximian.com
http://lists.ximian.com/mailman/listinfo/mono-devel-list
