I have an old patch with some simple speed-ups to the visited-link code. We can speed it up even more with some further design changes, but this is a small step in the right direction.
Created attachment 17530 [details] first cut, not sure it's ready for review yet
Created attachment 17763 [details] patch I really wanted to do the more complete fix that involves a hash table for things in global history, but this alone is a measurable speed-up so getting this in first.
Comment on attachment 17763 [details] patch r=me
Comment on attachment 17763 [details] patch Either there's a bug in form submission in TOT or I can't tell the difference between a + sign and nothingness.
Committed revision 28536.