[Dev-luatex] luafontloader virtual access (bug #404, #448)
Paweł Jackowski
P.Jackowski at gust.org.pl
Thu Sep 9 09:07:18 CEST 2010
Taco Hoekwater wrote:
[...]
> Hans and I just did some tests, and it seems that the userdata access
> is useful if *but only if* you are very low on memory. In other cases,
> it just adds extra objects to be garbage collected, which makes the
> collector slower. That is on top of extra time spent on the actual
> calls, and even worse: those extra gc objects tend to be scattered
> around in memory, resulting in extra minor page faults (cpu cache
> misses) and all that has a noticeable effect on run speed: the
> metatable-based access is 20-30% slower than the old massive to_table.
Interesting. As you said, much depends on how one uses / tests. I made
some tests with translating fontforge font structure directly into the
luatex font table without an intermediate form. This gives bests
results, but obviously requires too many simplifications.
> Therefore, there seems little point in expanding the metadata
> functionality any further. What is there will stay, but adding more
> metadata objects appears to be a waste of time on all sides.
OK, thank you.
--
Pawe/l Jackowski
P.Jackowski at gust.org.pl
More information about the dev-luatex
mailing list