Not to put too fine a point on it, TWiki needs a lot of work on performance. As of TWikiRelease04x00x00, here's what I think are the performance killers.

1. Code bloat. Compilation accounts for a heck of a lot of unaccelerated runtime.
   • I'll try LazyCompilation unless someone already has done that (and tells us the results). -- HaraldJoerg - 20 Apr 2006
2. Inefficient APIs loading down the code (e.g. beforeSaveHandler in Func).
3. TWikiPreferences - the whole "site-web-topic" scheme for preferences.
4. TWikiAccessControls are horrendously nasty, and need to be taken out of band.
5. Searching.

Beyond that, someone needs to try and precompile TWiki (I tried and failed).

Oh, and there's definitely scope for increased use of delayed evaluation using REST interfaces.

-- CrawfordCurrie - 15 Feb 2006

Could we get some actual measurements on any of this? Hard to know where to start otherwise.

-- MeredithLesly - 14 Apr 2006

i'm going to commit and updated version of the UserMapping change that I put into DEVELOP - its getting a 6-20% performance boost (measured by benchmark.pl). Bugs:Item1651

-- SvenDowideit - 21 Apr 2006

About measurements: I'm about to compile my thoughts of how to do MeasuringTWikiPerformance.

-- HaraldJoerg - 24 Apr 2006

There's a lot of existing material - don't forget it. See CategoryPerformance.

-- CrawfordCurrie - 25 Apr 2006

Thanks! There's also a short article about profiling (DynamicFunctionCoverage) and sort of a predecessor of MeasuringTWikiPerformance (ExaminingPerformance). Some articles which popped up in WebChangesForAllWebs due to adding the category, however, had their last content change in 2001 or 2002, I doubt they're useful for TWiki04x00Release...

-- HaraldJoerg - 28 Apr 2006

Lazy-loading of TWikiVariables does not appear to be a magic bullet. Sigh. Not that we really expected it to be, I guess.

-- MeredithLesly - 28 Apr 2006

One quick one might be to defaultly publish known to be static using PublishContrib or PublishWeb: automatic publish on save would suffice in many cases.

-- MartinCleaver - 03 May 2006

Another thing that would help is to send the editing gadget up with view. This way people can instantly edit because the browser has all the code it needs (including the raw text) to allow someone to start immediately.

-- MartinCleaver - 03 May 2006