[Gnumed-devel] xmlrpc performance

[Horst Herb]

My performance testing as attached below suggests that there is a ~0.05 sec 
overhead per call on a P4-1.7GHz when using XML-RPC instead of direct 
function calls. You can try it out on  your machine with the attached files.

This overhead will increase when we add authentication.

This is quite considerable., It highlichts that this technlogy is only useful 
for highest level calls - our design must not allow that more than 10 such 
calls per second user space real time are ever neccessary.

In order to not to penalize users with old hardware unneccessarily when they 
run all services on a local machine anyway, I would propose the following API 
design as demonstrated by this simple example:

if no_xmlrpc
        import myserver

def connect():
                return xmlrpclib.Server('http://localhost:8000')
        
if no_xmlrpc:
        server = myserver.PersonDB()
else:
        server = connect()

        server.GetPerson('1')

I am sure you get the drift. We have to make it transparent to the application 
whether XML-RPC is used or not - should be an option that is selectable at 
run-time. That way, we can have the benefits of both worlds, we a re 
future-compatible, we are open to communicate with other modules, but we 
still can have maximum performance should we chose it.

Horst
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address@hidden:~$ python myclient.py 10
Running a timed comparison of xmlrpc via direct function calls:
Each test is run 10 times
direct function calls
time elapsed:  0.000110030174255

XMLRPC, already connected to server
time elapsed:  0.056911945343

XMLRPC, reconnecting each time to server
time elapsed:  0.0517169237137

address@hidden:~$ python myclient.py 100
Running a timed comparison of xmlrpc via direct function calls:
Each test is run 100 times
direct function calls
time elapsed:  0.000619053840637

XMLRPC, already connected to server
time elapsed:  0.491975069046

XMLRPC, reconnecting each time to server
time elapsed:  0.494248986244

address@hidden:~$ python myclient.py 1000
Running a timed comparison of xmlrpc via direct function calls:
Each test is run 1000 times
direct function calls
time elapsed:  0.0076869726181

XMLRPC, already connected to server
time elapsed:  4.84028303623

XMLRPC, reconnecting each time to server
time elapsed:  4.93417906761

myserver.py
Description: Text Data

myclient.py
Description: Text Data