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 that we don't interrupt the merge session if
# a file-level merge failed
hg init repo
cd repo
echo foo > foo
echo a > bar
hg ci -Am 'add foo' -d '0 0'
hg mv foo baz
echo b >> bar
echo quux > quux1
hg ci -Am 'mv foo baz' -d '0 0'
hg up -qC 0
echo >> foo
echo c >> bar
echo quux > quux2
hg ci -Am 'change foo' -d '0 0'
# test with the rename on the remote side
HGMERGE=false hg merge
# test with the rename on the local side
hg up -C 1
HGMERGE=false hg merge
true