dirstate: track updated files to improve write time Previously, dirstate.write() would iterate over the entire dirstate to find any entries that needed to be marked 'lookup' (i.e. if they have the same timestamp as now). This was O(working copy) and slow in large repos. It was most visible when rebasing or histediting multiple commits, since it gets executed once per commit, even if the entire rebase/histedit is wrapped in a transaction. The fix is to track which files have been editted, and only check those to see if they need to be marked as 'lookup'. This saves 25% on histedit times in very large repositories. I tested this by adding temporary debug logic to verify that the old files processed in the loop matched the new files processed in the loop and running the test suite.

hook: give exthooks tags for blocking time The ui.system autogenerated tag isn't really useful - as they're named, let's use the name the user gave us.

filemerge: tag merge tool for blocked times Merge tools can take a while - let's ensure that they're appropriately tagged

hgk: set a blocked tag when the user invokes view

transplant: set a blockedtag when invoking external filter

config: set blockedtag when invoking configuration edit

bisect: set a blockedtag when running the check command So that the hg bisect data clearly shows the bisect command separately to the main data set.

dispatch: set a blockedtag when running an external alias

patch: set a blockedtag when running an external filter

sshpeer: set a blockedtag when starting ssh So that the data is readable.