Large .ass files result in slow mkvmerge startup since v39
$ set MKVMERGE_WIN '/mnt/c/Program Files/MKVToolNix/mkvmerge.exe'
$ set MKVMERGE_NIX /usr/bin/mkvmerge
$ $MKVMERGE_WIN --version
mkvmerge v49.0.0 ('Sick Of Losing Soulmates') 64-bit
$ $MKVMERGE_NIX --version
mkvmerge v37.0.0 ('Leave It') 64-bit
$ time $MKVMERGE_WIN -J amazingbig.ass
{"<snip>": "<snip>"}
________________________________________________________
Executed in 63.62 secs fish external
usr time 0.00 micros 0.00 micros 0.00 micros
sys time 0.00 micros 0.00 micros 0.00 micros
$ time $MKVMERGE_NIX -J amazingbig.ass
{"<snip>": "<snip>"}
________________________________________________________
Executed in 1.87 secs fish external
usr time 1796.88 millis 0.00 micros 1796.88 millis
sys time 78.12 millis 0.00 micros 78.12 millis
I was able to identify the issue in Windows builds starting with v39. Linux builds of v47 and v49 also show the issue, but to a reduced degree, with startup times on the order of 5-10 seconds rather than minutes. On Windows, mkvmerge amazingbig.ass -o amazingbig.mks
spends significantly more time starting up than it does displaying any sort of progress indicator.
(Yes, I am genuinely producing and using subtitle files with size somewhere around this magnitude. I often wish I wasn't.)
Edited by The0x539