[Moose-dev] Re: PetitParser performance

On Fri, Jan 30, 2015 at 9:36 PM, Sven Van Caekenberghe <sven(a)stfx.eu&gt; wrote: > Usman, this is a really cool bug report ! > Thanks :) > > > On 30 Jan 2015, at 16:36, Usman Bhatti <usman.bhatti(a)gmail.com&gt; wrote: > > > > Here is a script that shows the factor of 2 in time taken for parsing. > The idea of the script is to introduce several wrong branches before > hitting the correct one (originally proposed by Guillaume). > > > > |rule wrongBranches| > > [wrongBranches := (25 to: 45) inject: 24 asCharacter asParser into: > [:acc :each | acc / each asCharacter asParser]. > > rule := PPDelegateParser new. > > rule setParser: $a asParser / ((wrongBranches / $. asParser), rule). > > rule parse: (String streamContents: [ :s | > > 30000 timesRepeat: [s nextPut: $.]. s nextPut: $a ])] timeToRun > > > > > > Below are the graphs that were generated when varying the string length > provided to the above parser description. Green part shows the time taken > by the older version and the red part with the latest PP. > > > > <graph.png> > > > > Data values and graph generated by the script in the attached file. > > > > regards. > > > > usman > > > > On Fri, Jan 30, 2015 at 1:30 PM, Tudor Girba <tudor(a)tudorgirba.com&gt; > wrote: > > Hi, > > > > Hmm. I thought this was fixed and that you said at the end that the > performance penalty is no longer a factor of 2. > > > > Do you have a simple example for checking the simple case of 2x > performance loss? > > > > Doru > > > > > > On Fri, Jan 30, 2015 at 12:28 PM, Usman Bhatti <usman.bhatti(a)gmail.com&gt; > wrote: > > Hi, > > > > Since the work on the integration of PPContext in PetitParser, there is > significant performance degradation. I have already mentioned that on > simple grammar the factor is about 2. But on complex grammar (for example, > our proprietary parser for 4D language ), we have seen that degradation is > goes well beyond this factor. So, for example, for 800K lines that we parse > in under 10 minutes without PPContext work, with the latest version it goes > beyond 2h. > > > > I have not been able to reproduce my case on simple grammars. May be we > can have some benchmarks using open source parsers and large code bases > (e.g. PP Java Parser on JHotDraw or ArgoUML). > > > > Currently, I circumvent this issue by using PP v1.51 but I can provide > relevant feedback and run benches on any improvements. > > > > regards. > > > > Usman > > > > _______________________________________________ > > Moose-dev mailing list > > Moose-dev(a)iam.unibe.ch > > https://www.iam.unibe.ch/mailman/listinfo/moose-dev > > > > > > > > > > -- > > www.tudorgirba.com > > > > "Every thing has its own flow" > > > > _______________________________________________ > > Moose-dev mailing list > > Moose-dev(a)iam.unibe.ch > > https://www.iam.unibe.ch/mailman/listinfo/moose-dev > > > > > > <script-graph.txt>_______________________________________________ > > Moose-dev mailing list > > Moose-dev(a)iam.unibe.ch > > https://www.iam.unibe.ch/mailman/listinfo/moose-dev > > > _______________________________________________ > Moose-dev mailing list > Moose-dev(a)iam.unibe.ch > https://www.iam.unibe.ch/mailman/listinfo/moose-dev > _______________________________________________ Moose-dev mailing list Moose-dev(a)iam.unibe.ch https://www.iam.unibe.ch/mailman/listinfo/moose-dev