view tests/svn/svndump-empty.sh @ 18063:34a1a639d835

revset.children: ignore rev numbers that are too low

This replaces unnecessary parentrevs() calls with calculating min(parentset).
Even though the min operation is O(size of parentset), since parentrevs is
relatively expensive, this tradeoff almost always works in our favour. In a
repository with over 400,000 changesets, hg perfrevset "children(X)" takes:

       Set X       Before    After
       -1           0.51s    0.06s
    -1000:          0.55s    0.08s
   -10000:          0.56s    0.10s
  -100000:          0.60s    0.25s
  -100000:-99000    0.55s    0.19s
        0:100000    0.60s    0.61s
      all()         0.72s    0.74s

The relative performance is similar for Mercurial's own repository -- several
times faster in most cases, slightly slower for revisions close to 0 and
all().

#!/bin/sh
#
# Use this script to generate empty.svndump
#

mkdir temp
cd temp

mkdir project-orig
cd project-orig
mkdir trunk
mkdir branches
mkdir tags
cd ..

svnadmin create svn-repo
svnurl=file://`pwd`/svn-repo
svn import project-orig $svnurl -m "init projA"

svn co $svnurl project
cd project
mkdir trunk/dir
echo a > trunk/dir/a
svn add trunk/dir
svn ci -m adddir

echo b > trunk/b
svn add trunk/b
svn ci -m addb

echo c > c
svn add c
svn ci -m addc
cd ..

# svnsync repo/trunk/dir only so the last two revisions are empty
svnadmin create svn-empty
cat > svn-empty/hooks/pre-revprop-change <<EOF
#!/bin/sh
exit 0
EOF
chmod +x svn-empty/hooks/pre-revprop-change
svnsync init --username svnsync file://`pwd`/svn-empty file://`pwd`/svn-repo/trunk/dir
svnsync sync file://`pwd`/svn-empty
svn log -v file://`pwd`/svn-empty

svnadmin dump svn-empty > ../empty.svndump