[poppler] [patch] improving poppler performance

[Albert Astals Cid]

A Dilluns, 23 d'agost de 2010, Paweł Wiejacha va escriure:
> Hi,
> 05_bigger_glyph_pixmap_cache.patch
> Previously glyph cache hit rate was about 10-20%. Increasing its size 6
> times (up to 1.5 MB additional memory) results in 30-60% hit rate and
> 3-12% performance increase.

I've commited a different approach for this that should almost not increase 
memory usage.

My approach is increasing the cache size only for small fonts (those with 
glyphsize < 128 or < 64)

My reasoning here is that if the fonts are big the will not be lots of them in 
the same page (because they won't fit) thus the improvement given by 
increasing the cache size won't be much in absolute time, that is, all the pdf 
i have with "just text" on the page, render in 60ms, increasing the cache size 
will give us a some speed increase, but 60ms is "fast enough".

The only "very font intensive" pdf i have found in my collection is the 
firefox nytimes advertisement that has a HUGE amount of small text, thus my 
change makes it go from 1500ms to 1250ms.

I've looked at the pdf you supplied and none of them seemed a very font 
intensive file.

I'd love if anyone can supply a very font intensive pdf that is not the 
firefox nytimes advertisement.

Albert