[luatex] [lltx] pattern loading in luatex

[Stephan Hennig]

[CC'ing luatex list]

Thanks to you and Ulrike and sorry for the late reply!

schrieb Manuel Pégourié-Gonnard:
> Le 24/02/2011 10:33, Stephan Hennig a écrit :
>> 
>> With LuaTeX being able to load patterns at run-time, there are now
>> three different pattern loading strategies possible (that I can
>> think of):
>> 
>>   1.  Load all patterns ...
>> 
> I'm afraid "load" is too imprecise to precisely describe what happens with
> LuaTeX. There are now two possibly distinct operations:
> a. read the patterns (as a string of characters)
> b. process them into a form usable by *TeX (a trie)

OK.


> With LuaTeX you have two options:
> 
> 1. Read all patterns at initex time and store them as a string of characters in
> the format; process them all at startup when the format is loaded.
> 2. Read and process requested patterns on demand.
> 
> Option 1 was used up to TeX Live 2009 and resulted in a long startup time.

AFAIK, LuaTeX uses a more complex trie with pre-calculated fall-back
states.  Are there any numbers about what makes loading and processing
(many) patterns in LuaTeX slow?  Is it the first stage of building the
traditional pattern trie from text files or is it the calculation of
fall-back states afterwards?


> Option 2 is implemented since TL 2010.

Great!  Somehow I happened to followed that back then, but missed what
it was all about. :/

Best regards,
Stephan Hennig