Nathan Ingersoll wrote: > Doing some profiling, I noticed that I was seeing a fair amount of > overhead (19.9% of the test apps completion time) coming from strcmp, > and in particular from calls to edje_file_data_get. This isn't > completely unexpected as EWL uses data keys in the edje to map widgets > to edje collections, but it had me wondering why there were so many > comparisons relative to other hot paths in the code. > > The problem became clear when I saw how data lookups were being done, > a linear scan of a list doing strcmp against each key in the list > until a match was found. With each search being O(n), this could add > up quickly. Since we are using key/value pairs for the data > association, a hash seemed more appropriate. > > To test this without breaking the file format, I added a cache to the > edje file struct and populated it immediately after reading the file > by moving data out of the list and into the hash. Using the new hash I > re-ran my test and saw an improvement of 18.5%, and basically > eliminating almost the entire time spent in edje_file_data_get. > Just my 2 cents, but with gains like that how can we NOT use a hash :)
> While I don't expect to see a huge improvement, this would be more > efficient using a hash directly in the eet. The downside would be that > compatibility would be broken for existing edje's. > Such is the way with pre-alpha code...things break. Theme/edj authors will just have to deal with it I suppose. I'm sure at some point there will be another breakage after this one before things start to settle. > So that finally brings me to my questions: what is the current policy > on breaking edje compatibility? and does anyone have an objection to > moving the data storage to be a hash rather than a list? > I say if it's more efficient, go for it...tho imho we should wait until "old man" has a chance to chime in :) > Thanks, > Nathan > Cheers, dh ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ enlightenment-devel mailing list enlightenment-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/enlightenment-devel
