<christian.benien@gmail.com> wrote in message
news:1124048651.356472.44630@g43g2000cwa.googlegroups.com...
> We currently see the following behaviour in our main process (under
> high load)
>
> - All threads are suspended
> - Performance counters don't publish any data
> - 0% CPU usage (all CPU goes to other processes)
>
> This sometimes goes on for 10-20 seconds. We do a lot of I/O (network
> and disk), P/Invoke, and the process itself uses approx. 75% of the
> system's CPU. I can reproduce the above mentioned condition easily when
> I start another CPU-intensive task like a benchmark, although it
> happens sporadically anyway.
>
> Can this be caused by the garbage collector? I know that it suspends
> all threads for a collection, but for so long? And why don't I see
> anything in the performance counters? I don't even see a hint and then
> suddenly the process hangs and no performance data is available.
>
> Any help would be appreciated!
>
> Christian
>

<christian.benien@gmail.com> wrote in message
news:1124088686.879721.316590@f14g2000cwb.googlegroups.com...
> The problem is that the application is (almost) realtime. We can handle
> delays of 3-4 seconds, but nothing more than that. The problem with
> counting collections is that from the point where the process is
> suspended, I don't get any performance data at all! I'm monitoring
> every ".NET CLR Memory" counter that's available.
>
> Is there any specific counter that could indicate what's going on after
> the process resumes?
>

<christian.benien@gmail.com> wrote in message
news:1124171235.184386.54880@g14g2000cwa.googlegroups.com...
> Alvin,
>
> thanks for your help. But I think I finally figured it out. The reason
> was that we allocated a lot of byte[] objects for async network I/O. If
> you pass them to Socket.BeginReceive, they are promoted to gen 2 in the
> GC. The network throughput in my test case was about 30-40 Mbit, so in
> effect we allocated more than 10 MB per second.
>
> Now I try to reuse the buffer whenever possible, and since then I no
> more problems. So it was clearly the GC, but I was very surprised to
> see that it can take so long.
>
> Regards,
> Christian
>