revlog: break up compression of large deltas
Python's zlib apparently makes an internal copy of strings passed to
compress(). To avoid this, compress strings 1M at a time, then join
them at the end if the result would be smaller than the original.
For initial commits of large but compressible files, this cuts peak
memory usage nearly in half.
#!/bin/sh
# test children command
cat <<EOF >> $HGRCPATH
[extensions]
hgext.children=
EOF
echo "% init"
hg init t
cd t
echo "% no working directory"
hg children
echo % setup
echo 0 > file0
hg ci -qAm 0 -d '0 0'
echo 1 > file1
hg ci -qAm 1 -d '1 0'
echo 2 >> file0
hg ci -qAm 2 -d '2 0'
hg co null
echo 3 > file3
hg ci -qAm 3 -d '3 0'
echo "% hg children at revision 3 (tip)"
hg children
hg co null
echo "% hg children at nullrev (should be 0 and 3)"
hg children
hg co 1
echo "% hg children at revision 1 (should be 2)"
hg children
hg co 2
echo "% hg children at revision 2 (other head)"
hg children
for i in null 0 1 2 3; do
echo "% hg children -r $i"
hg children -r $i
done
echo "% hg children -r 0 file0 (should be 2)"
hg children -r 0 file0
echo "% hg children -r 1 file0 (should be 2)"
hg children -r 1 file0
hg co 0
echo "% hg children file0 at revision 0 (should be 2)"
hg children file0