Per-page adaptive parse skip: once mwparserfromhell times out on a
revision of size N bytes, force-timeout future revisions on the same
page whose text is >= N bytes instead of waiting another 60s on each
one. State resets per page, so well-behaved pages are unaffected.
Motivated by zhwiki bot-vandalism log pages (e.g. ns=4
'Wikipedia:当前的破坏/...' at 4.6GB across 6133 revisions) where every
revision triggers the 60s SIGALRM, blocking the worker for hours.
72410d090b