> What limits the rate that poll_func is called in a python frontend? 

First the general advice: if you reduce the "period" of your equipment, then your function will get called more frequently. You can set it to 0 and we'll call it as often as possible. You can set this in the ODB at "/Equipment/Python Data Simulator/Common/Period"

If that's still not fast enough, then you can return a *list* of events from your readout_func. I've seen real-world cases of 25kHz+ of midas events generated in this fashion.


However in your case the limitation is likely that you're sending 1.25MB per event and we have a lot of data marshalling to do between the python and C++ layer. In particular it takes 15ms on my machine to just pack the data into a memory buffer (see timeit command below). I am sure there must be a faster way to do this packing, especially in the case where the bank contains a numpy array rather than a python list.

I'll add it to my to-do list to investigate improving the performance of medium-to-large events in the python code.


Cheers,
Ben


P.S. You may have a bug in your calculations (depending on how you did your testing). In poll_func I think you should be updating the stats every time the function is called, not just the times when you return True.


P.P.S. Command I used to test how slow it is to pack the data. One-time setup of creating the buffers, then multiple tests of the pack_into function:

python -m timeit -s "import struct;import ctypes;arr = [0]*1250001;buf = ctypes.create_string_buffer(10000000);fmt = \">1250000d\"" "struct.pack_into(fmt, buf, *arr)"
20 loops, best of 5: 15.3 msec per loop