[zeromq-dev] Windows throughput perfomance. Once again.

[Martin Sustrik]

Hi Gennadiy,

> I've already posted this issue a month ago, but it was stuck, so I want
> to up that thread with some additions.
> So, the issue was about very low performance charts under Windows, using
> tests in perf directory.

The problem with Windows is that's it's a proprietary OS. So, for 
example, I don't have two windows boxes to test on them, same way as I 
don't have HP-UX or AIX boxes. It's up to those with appropriate 
licenses to optimise 0MQ for those platforms.

> I make some new test since then, with a couple of linux boxes, so what I
> have now:
> Box running remote_thr is a sender(S), and box running local_thr is a
> receiver(R).
> Packet sizes are from 64 bytes to 256 Kbytes.
> Win(S) --> Win(R) - 10-50 Mbit/s
> Win(S) -->Linux(R) - 150-750 Mbit/s (varies mostly with packet size.
> Larger the packet - more throughput)
> Linux(S) -->Win(R) - 450-900 Mbit/s (much more stable results except for
> 64 byte blocks)
> Linux(S) --> Linux(R) - 800-950 Mbit/s (very low dispersion and the
> highest speed).

That sounds pretty bad. More investigation is needed.

> All Windows are WinXP SP3. Applications was built by VS2008 with no
> changes in projects in release mode.
> Tests were made in every data flow way, so network problems are excluded
> from list.
> So what would your suggestions?

What's needed is profiling of individual pieces of the critical path. 
That should show which piece is the bottleneck and should be optimised.

Martin