bdiff: switch to lyhash lyhash is a very simple and fast hash function that had the fewest hash collisions on a 3.9M line text corpus and 190k line binary corpus and should have significantly fewer collisions than the current hash function.

#!/bin/sh

mkdir a
cd a
hg init
echo 123 > a
hg add a
hg commit -m "a" -u a -d "1000000 0"

cd ..
mkdir b
cd b
hg init
echo 321 > b
hg add b
hg commit -m "b" -u b -d "1000000 0"

hg pull ../a
hg pull -f ../a
hg heads