branchcache: skip entries that are topological heads in the on disk file
In the majority of cases, topological heads are also branch heads. We have
efficient way to get the topological heads and efficient way to retrieve
their branch information. So there is little value in putting them in the branch
cache file explicitly. On the contrary, writing them explicitly tend to create
very large cache file that are inefficient to read and update.
So the branch cache v3 format is no longer including them. This changeset focus
on the format aspect and have no focus on the performance aspect. We will cover
that later.
#require no-windows
$ . "$TESTDIR/remotefilelog-library.sh"
$ hg init master
$ cd master
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> server=True
> EOF
$ echo x > x
$ echo y > y
$ echo z > z
$ hg commit -qAm xy
$ cd ..
$ hgcloneshallow ssh://user@dummy/master shallow -q
3 files fetched over 1 fetches - (3 misses, 0.00% hit ratio) over *s (glob)
$ cd shallow
Verify corrupt cache handling repairs by default
$ hg up -q null
$ chmod u+w $CACHEDIR/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/1406e74118627694268417491f018a4a883152f0
$ echo x > $CACHEDIR/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/1406e74118627694268417491f018a4a883152f0
$ hg up tip
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
Verify corrupt cache error message
$ hg up -q null
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> validatecache=off
> EOF
$ chmod u+w $CACHEDIR/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/1406e74118627694268417491f018a4a883152f0
$ echo x > $CACHEDIR/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/1406e74118627694268417491f018a4a883152f0
$ hg up tip 2>&1 | grep -E "^[^ ].*unexpected remotefilelog"
abort: unexpected remotefilelog header: illegal format
Verify detection and remediation when remotefilelog.validatecachelog is set
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> validatecachelog=$PWD/.hg/remotefilelog_cache.log
> validatecache=strict
> EOF
$ chmod u+w $CACHEDIR/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/1406e74118627694268417491f018a4a883152f0
$ echo x > $CACHEDIR/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/1406e74118627694268417491f018a4a883152f0
$ hg up tip
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
$ cat .hg/remotefilelog_cache.log
corrupt $TESTTMP/hgcache/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/1406e74118627694268417491f018a4a883152f0 during contains
Verify handling of corrupt server cache
$ rm -f ../master/.hg/remotefilelogcache/y/076f5e2225b3ff0400b98c92aa6cdf403ee24cca
$ touch ../master/.hg/remotefilelogcache/y/076f5e2225b3ff0400b98c92aa6cdf403ee24cca
$ clearcache
$ hg prefetch -r .
3 files fetched over 1 fetches - (3 misses, 0.00% hit ratio) over *s (glob)
$ test -s ../master/.hg/remotefilelogcache/y/076f5e2225b3ff0400b98c92aa6cdf403ee24cca
$ hg debugremotefilelog $CACHEDIR/master/95/cb0bfd2977c761298d9624e4b4d4c72a39974a/076f5e2225b3ff0400b98c92aa6cdf403ee24cca
size: 2 bytes
path: $TESTTMP/hgcache/master/95/cb0bfd2977c761298d9624e4b4d4c72a39974a/076f5e2225b3ff0400b98c92aa6cdf403ee24cca
key: 076f5e2225b3
node => p1 p2 linknode copyfrom
076f5e2225b3 => 000000000000 000000000000 f3d0bb0d1e48