Phase stats sync assertion error

[Alex Rousskov]

On 05/09/2017 06:02 PM, William Law wrote:
> On 05/09/2017, Alex Rousskov wrote:
>> Is it possible that you have more than ~30 Polygraph processes
>> participating in a test?

> I was running more than that and ended up reducing the count to try and
> stabilise it.  I think it finally steadied at about 20 server processes.
> We are looking to *really* stress proxy/firewall devices (e.g. >10Gbit
> hopefully) so really cranking this up on both client and server side.

That probably explains it then. IIRC, it is not just the server
processes that count because client processes exchange phase information
among them as well (via servers) Please try to work around this problem
by increasing the hard-coded limit (search for 37 in
src/runtime/StatPhaseSync.cc) and recompiling Polygraph. Changing 37 to
some prime number like 97 or even 199 may work well. Please let us know
if that helps, and we will work on removing the hard-coded limit.


>> Why are you using --worker if you are not running SMP tests?
> 
> That was worker xx out of 70 :D  We have a script that spawns a heap of
> servers and clients with a defined test config, then cleans up afterwards.

Please note that starting individual workers on your own is not
officially supported -- the interface between the master process and
workers may change without notice, and those changes may affect your
setup. When you get a chance, consider adding a proper SMP Bench
configuration to your workload so that Polygraph starts workers based on
your test configuration.


Thank you,

Alex.