view contrib/showstack.py @ 28390:48e1a641765d stable

obsolete: fix n^2 marker computation behavior

Previously, if you ran obsolete.createmarkers with a bunch of markers that did
not have successors (like when you do a prune), it encountered a n^2 computation
behavior because the loop would read the changelog (to get ctx.parents()), then
add a marker, in a loop.  Adding a marker invalidated the computehidden cache,
and reading the changelog recomputed it.

This resulted in pruning 150 commits taking 150+ seconds in a large repo.

The fix is to break the reading part of the loop to be separate from the writing
part.

# showstack.py - extension to dump a Python stack trace on signal
#
# binds to both SIGQUIT (Ctrl-\) and SIGINFO (Ctrl-T on BSDs)

import sys, signal, traceback

def sigshow(*args):
    sys.stderr.write("\n")
    traceback.print_stack(args[1], limit=10, file=sys.stderr)
    sys.stderr.write("----\n")

def extsetup(ui):
    signal.signal(signal.SIGQUIT, sigshow)
    try:
        signal.signal(signal.SIGINFO, sigshow)
    except AttributeError:
        pass