Optimize manifest.add Testing shows that manifest.add is spending a significant percentage of its time running calcoffsets and doing text = "".join(addlist). This patch removes the need for both of these by storying the manifest in a character array, and using a modified bisect search to find lines without the help of a separate index of line offsets. manifest.add was also reworked to push delta construction/combination into the main loop. Time to apply 2751 patches (without psyco, ext3 noatime,data=writeback): Stock hg: 4m45s real 3m32s user 55s sys patched: 2m48s real 1m53s user 43s sys quilt: 2m30s real 45s user 50s sys (quilt does much more io...)

#!/bin/sh

hg init
echo foo > a
hg add a
hg commit -m "1" -d "0 0"
hg verify
chmod -r .hg/data/a.d
hg verify 2>/dev/null || echo verify failed
chmod +r .hg/data/a.d
hg verify 2>/dev/null || echo verify failed
chmod -w .hg/data/a.d
echo barber > a
hg commit -m "2" -d "0 0" 2>/dev/null || echo commit failed