System.OutOfMemoryException: Exception of type 'System.OutOfMemoryException' was thrown.

[ibettio1]

We have an application that receives phone calls (Linux), that's currently deployed to different environments on Kubernetes clusters (Azure). Lately we have been experiencing this exception for only one environment:

[17:42:39 ERR] Exception SIPUDPChannel EndReceiveFrom. Exception of type 'System.OutOfMemoryException' was thrown.
System.OutOfMemoryException: Exception of type 'System.OutOfMemoryException' was thrown.
at System.Collections.Concurrent.ConcurrentQueueSegment1..ctor(Int32 boundedLength) at System.Collections.Concurrent.ConcurrentQueue1.EnqueueSlow(T item)
at SIPSorcery.SIP.SIPTransport.ReceiveMessage(SIPChannel sipChannel, SIPEndPoint localEndPoint, SIPEndPoint remoteEndPoint, Byte[] buffer)
at SIPSorcery.SIP.SIPUDPChannel.EndReceiveFrom(IAsyncResult ar)

Even though it's an OOM exception, the containers still have some memory available, usually around 20% free. This may be lacking in details, but does anyone have suggestions on where to look or what other information I could provide to help identify what's the problem?

[sipsorcery]

It seems the SIP transport queue is not getting processed fast enough and therefore the queued messages are consuming extra memory.

Assuming your serivce is Internet facing due you have any way of monitoring incoming SIP traffic? Script kidcies constantly scan for SIP services and will eventually subject them to an exploit attempt. If your service has been running for more than a month or so it would be very surprising if you haven't already seen this behaviour.

[ElDuderinoBerlin]

The CLR is not capable of allocating the whole virtual memory left. That's by design.

1. use x64-platform, if not
2. higher the memory avail
3. higher processing power of your machines, root server, VPS or whatever
4. use NET framework >= 8.0 for aggressive optimizations built in
5. secure SIP-ports if possible against attacks (overflowing queues)

Regards
Martin