tests/test-remotefilelog-gcrepack.t
author Pierre-Yves David <pierre-yves.david@octobus.net>
Mon, 20 May 2019 10:06:53 +0200
branchstable
changeset 42167 d2c871b78c36
parent 40761 0800d9e6e216
child 42375 f22131315791
permissions -rw-r--r--
bookmark: add a test for a race condition on push Bookmark pointing to unknown nodes are ignored. Later these ignored bookmarks are dropped when writing the file back on disk. On paper, this behavior should be fine, but with the current implementation, it can lead to unexpected bookmark deletions. In theory, to make sure writer as a consistent view, taking the lock also invalidate bookmark data we already loaded into memory. However this invalidation is incomplete. The data are stored in a `filecache` that preserve them if the bookmark related file are untouched. In practice, the bookmark data in memory also depends of the changelog content, because of the step checking if the bookmarks refers to a node known to the changelog. So if the bookmark data were loaded from an up to date bookmark file but filtered with an outdated changelog file this go undetected. This condition is fairly specific, but can occurs very often in practice. We introduce a test recreating the situation. The test comes in an independant changeset to show it actually reproduce the situation. The fix will come soon after. A large share of the initial investigation of this race condition was made by Valentin Gatien-Baron <valentin.gatienbaron@gmail.com>.

#require no-windows

  $ . "$TESTDIR/remotefilelog-library.sh"

  $ hg init master
  $ cd master
  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > server=True
  > EOF
  $ echo x > x
  $ hg commit -qAm x
  $ echo y > y
  $ rm x
  $ hg commit -qAm DxAy
  $ echo yy > y
  $ hg commit -qAm y
  $ cd ..

  $ hgcloneshallow ssh://user@dummy/master shallow -q
  1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)

# Set the prefetchdays config to zero so that all commits are prefetched
# no matter what their creation date is.
  $ cd shallow
  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > prefetchdays=0
  > EOF
  $ cd ..

# Prefetch all data and repack

  $ cd shallow
  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > bgprefetchrevs=all()
  > EOF

  $ hg prefetch
  2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
  $ hg repack
  $ sleep 0.5
  $ hg debugwaitonrepack >/dev/null 2>%1

  $ find $CACHEDIR | sort | grep ".datapack\|.histpack"
  $TESTTMP/hgcache/master/packs/7bcd2d90b99395ca43172a0dd24e18860b2902f9.histpack
  $TESTTMP/hgcache/master/packs/dc8f8fdc76690ce27791ce9f53a18da379e50d37.datapack

# Ensure that all file versions were prefetched

  $ hg debugdatapack `ls -ct $TESTTMP/hgcache/master/packs/*.datapack | head -n 1`
  $TESTTMP/hgcache/master/packs/dc8f8fdc76690ce27791ce9f53a18da379e50d37:
  x:
  Node          Delta Base    Delta Length  Blob Size
  1406e7411862  000000000000  2             2
  
  Total:                      2             2         (0.0% bigger)
  y:
  Node          Delta Base    Delta Length  Blob Size
  50dbc4572b8e  000000000000  3             3
  076f5e2225b3  50dbc4572b8e  14            2
  
  Total:                      17            5         (240.0% bigger)

# Test garbage collection during repack

  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > bgprefetchrevs=tip
  > gcrepack=True
  > nodettl=86400
  > EOF

  $ hg repack
  $ sleep 0.5
  $ hg debugwaitonrepack >/dev/null 2>%1

  $ find $CACHEDIR | sort | grep ".datapack\|.histpack"
  $TESTTMP/hgcache/master/packs/7bcd2d90b99395ca43172a0dd24e18860b2902f9.histpack
  $TESTTMP/hgcache/master/packs/a4e1d094ec2aee8a08a4d6d95a13c634cc7d7394.datapack

# Ensure that file 'x' was garbage collected. It should be GCed because it is not in the keepset
# and is old (commit date is 0.0 in tests). Ensure that file 'y' is present as it is in the keepset.

  $ hg debugdatapack `ls -ct $TESTTMP/hgcache/master/packs/*.datapack | head -n 1`
  $TESTTMP/hgcache/master/packs/a4e1d094ec2aee8a08a4d6d95a13c634cc7d7394:
  y:
  Node          Delta Base    Delta Length  Blob Size
  50dbc4572b8e  000000000000  3             3
  
  Total:                      3             3         (0.0% bigger)

# Prefetch all data again and repack for later garbage collection

  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > bgprefetchrevs=all()
  > EOF

  $ hg prefetch
  2 files fetched over 1 fetches - (2 misses, 0.00% hit ratio) over *s (glob)
  $ hg repack
  $ sleep 0.5
  $ hg debugwaitonrepack >/dev/null 2>%1

  $ find $CACHEDIR | sort | grep ".datapack\|.histpack"
  $TESTTMP/hgcache/master/packs/7bcd2d90b99395ca43172a0dd24e18860b2902f9.histpack
  $TESTTMP/hgcache/master/packs/dc8f8fdc76690ce27791ce9f53a18da379e50d37.datapack

# Ensure that all file versions were prefetched

  $ hg debugdatapack `ls -ct $TESTTMP/hgcache/master/packs/*.datapack | head -n 1`
  $TESTTMP/hgcache/master/packs/dc8f8fdc76690ce27791ce9f53a18da379e50d37:
  x:
  Node          Delta Base    Delta Length  Blob Size
  1406e7411862  000000000000  2             2
  
  Total:                      2             2         (0.0% bigger)
  y:
  Node          Delta Base    Delta Length  Blob Size
  50dbc4572b8e  000000000000  3             3
  076f5e2225b3  50dbc4572b8e  14            2
  
  Total:                      17            5         (240.0% bigger)

# Test garbage collection during repack. Ensure that new files are not removed even though they are not in the keepset
# For the purposes of the test the TTL of a file is set to current time + 100 seconds. i.e. all commits in tests have
# a date of 1970 and therefore to prevent garbage collection we have to set nodettl to be farther from 1970 than we are now.

  $ cat >> .hg/hgrc <<EOF
  > [remotefilelog]
  > bgprefetchrevs=
  > nodettl=$(($(date +%s) + 100))
  > EOF

  $ hg repack
  $ sleep 0.5
  $ hg debugwaitonrepack >/dev/null 2>%1

  $ find $CACHEDIR | sort | grep ".datapack\|.histpack"
  $TESTTMP/hgcache/master/packs/7bcd2d90b99395ca43172a0dd24e18860b2902f9.histpack
  $TESTTMP/hgcache/master/packs/dc8f8fdc76690ce27791ce9f53a18da379e50d37.datapack

# Ensure that all file versions were prefetched

  $ hg debugdatapack `ls -ct $TESTTMP/hgcache/master/packs/*.datapack | head -n 1`
  $TESTTMP/hgcache/master/packs/dc8f8fdc76690ce27791ce9f53a18da379e50d37:
  x:
  Node          Delta Base    Delta Length  Blob Size
  1406e7411862  000000000000  2             2
  
  Total:                      2             2         (0.0% bigger)
  y:
  Node          Delta Base    Delta Length  Blob Size
  50dbc4572b8e  000000000000  3             3
  076f5e2225b3  50dbc4572b8e  14            2
  
  Total:                      17            5         (240.0% bigger)