[Embedlets-dev] Making progress on the TINI....

[Andrzej J. T. <an...@ch...>]

It was bugging me, so I did some investigation, and found that one particular 
operation was killing the TINI performance, and that was accessing various 
component property values during the event propagation process.  I refactored 
that so that Components (eg. Embedlets) cache their static values in instance 
variables (things like the unique ID, description, version, etc.) and also 
refactored how Lifecycle state was get/set in a similar manner.

Here were the results, comparing async and sync event propagation (all values 
in events/second)  before and after the refactorings:

PLATFORM        ASYNC      SYNC (Recycled)   SYNC (Non-Recycled)

TINI (before):            8                 13                          143
TINI (after):             12                 71                          133

As you can see, the Async speed improved by 50%.  The Sync speed using 
recycled event instances (so only one is ever created) was markedly improved 
by the refactoring. The Sync (Non-recycled) slowed down a trifle due to some 
other refactoring that I put in place to improve the Embedlet spec interfaces 
a bit, but the net loss in speed was only about 7% (and those structural 
refactorings were necessary).

I figure the SYNC (Non-Recycled) is running about as fast as the poor TINI 
can go, and though there might be some minor tweaking that could possibly 
help a bit, that's about all she wrote.  With the new refactorings, the SYNC 
(Recycled) path is probably approaching optimum as well.

However, the Async is still quite disappointing.  Sure it's using threads and 
thread context switches, but I think it should be a bit closer to the  SYNC 
(Recycled) performance.  My gut feel is that this can probably be improved a 
fair bit by optimizing the queue structures (away from generic Vectors and 
Hashtables to more customized versions that are specifically tuned to the 
access patterns that async event propagation produces).  So there is still 
lots of room there I think.





Andrzej Jan Taramina
Chaeron Corporation: Enterprise System Solutions
http://www.chaeron.com