tests/test-lfs-test-server.t

bundle2: inline changegroup.readexactly()

Profiling reveals this loop is pretty tight. Literally any
function call elimination can make a big difference.

This commit inlines the relatively trivial changegroup.readexactly()
method inside the loop.

The results with `hg perfbundleread` on a bundle of the Firefox repo
speak for themselves:

! read(8k)
! wall 0.679730 comb 0.680000 user 0.140000 sys 0.540000 (best of 15)
! read(16k)
! wall 0.577228 comb 0.570000 user 0.080000 sys 0.490000 (best of 17)
! read(32k)
! wall 0.516060 comb 0.520000 user 0.040000 sys 0.480000 (best of 20)
! read(128k)
! wall 0.496378 comb 0.490000 user 0.010000 sys 0.480000 (best of 20)
! bundle2 iterparts()
! wall 3.460903 comb 3.460000 user 2.760000 sys 0.700000 (best of 3)
! wall 3.056811 comb 3.050000 user 2.340000 sys 0.710000 (best of 4)
! bundle2 iterparts() seekable
! wall 4.312722 comb 4.310000 user 3.480000 sys 0.830000 (best of 3)
! wall 4.007676 comb 4.000000 user 3.170000 sys 0.830000 (best of 3)
! bundle2 part seek()
! wall 6.754764 comb 6.740000 user 3.970000 sys 2.770000 (best of 3)
! wall 6.267110 comb 6.250000 user 3.480000 sys 2.770000 (best of 3)
! bundle2 part read(8k)
! wall 3.668004 comb 3.660000 user 2.960000 sys 0.700000 (best of 3)
! wall 3.404164 comb 3.400000 user 2.650000 sys 0.750000 (best of 3)
! bundle2 part read(16k)
! wall 3.489196 comb 3.480000 user 2.750000 sys 0.730000 (best of 3)
! wall 3.197972 comb 3.200000 user 2.490000 sys 0.710000 (best of 4)
! bundle2 part read(32k)
! wall 3.388569 comb 3.380000 user 2.640000 sys 0.740000 (best of 3)
! wall 3.060557 comb 3.060000 user 2.340000 sys 0.720000 (best of 4)
! bundle2 part read(128k)
! wall 3.276415 comb 3.270000 user 2.560000 sys 0.710000 (best of 4)
! wall 2.952209 comb 2.950000 user 2.230000 sys 0.720000 (best of 4)

Differential Revision: https://phab.mercurial-scm.org/D1392

Require lfs-test-server (https://github.com/git-lfs/lfs-test-server)

  $ hash lfs-test-server || { echo 'skipped: missing lfs-test-server'; exit 80; }

  $ LFS_LISTEN="tcp://:$HGPORT"
  $ LFS_HOST="localhost:$HGPORT"
  $ LFS_PUBLIC=1
  $ export LFS_LISTEN LFS_HOST LFS_PUBLIC
  $ lfs-test-server &> lfs-server.log &
  $ echo $! >> $DAEMON_PIDS

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > lfs=
  > [lfs]
  > url=http://foo:bar@$LFS_HOST/
  > threshold=1
  > EOF

  $ hg init repo1
  $ cd repo1
  $ echo THIS-IS-LFS > a
  $ hg commit -m a -A a

  $ hg init ../repo2
  $ hg push ../repo2 -v
  pushing to ../repo2
  searching for changes
  lfs: uploading 31cf46fbc4ecd458a0943c5b4881f1f5a6dd36c53d6167d5b69ac45149b38e5b (12 bytes)
  1 changesets found
  uncompressed size of bundle content:
       * (changelog) (glob)
       * (manifests) (glob)
       *  a (glob)
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files

  $ cd ../repo2
  $ hg update tip -v
  resolving manifests
  getting a
  lfs: downloading 31cf46fbc4ecd458a0943c5b4881f1f5a6dd36c53d6167d5b69ac45149b38e5b (12 bytes)
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

When the server has some blobs already

  $ hg mv a b
  $ echo ANOTHER-LARGE-FILE > c
  $ echo ANOTHER-LARGE-FILE2 > d
  $ hg commit -m b-and-c -A b c d
  $ hg push ../repo1 -v | grep -v '^  '
  pushing to ../repo1
  searching for changes
  lfs: need to transfer 2 objects (39 bytes)
  lfs: uploading 37a65ab78d5ecda767e8622c248b5dbff1e68b1678ab0e730d5eb8601ec8ad19 (20 bytes)
  lfs: uploading d11e1a642b60813aee592094109b406089b8dff4cb157157f753418ec7857998 (19 bytes)
  1 changesets found
  uncompressed size of bundle content:
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 3 changes to 3 files

  $ hg --repo ../repo1 update tip -v
  resolving manifests
  getting b
  getting c
  lfs: downloading d11e1a642b60813aee592094109b406089b8dff4cb157157f753418ec7857998 (19 bytes)
  getting d
  lfs: downloading 37a65ab78d5ecda767e8622c248b5dbff1e68b1678ab0e730d5eb8601ec8ad19 (20 bytes)
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved

Check error message when the remote missed a blob:

  $ echo FFFFF > b
  $ hg commit -m b -A b
  $ echo FFFFF >> b
  $ hg commit -m b b
  $ rm -rf .hg/store/lfs
  $ hg update -C '.^'
  abort: LFS server claims required objects do not exist:
  8e6ea5f6c066b44a0efa43bcce86aea73f17e6e23f0663df0251e7524e140a13!
  [255]

Check error message when object does not exist:

  $ hg init test && cd test
  $ echo "[extensions]" >> .hg/hgrc
  $ echo "lfs=" >> .hg/hgrc
  $ echo "[lfs]" >> .hg/hgrc
  $ echo "threshold=1" >> .hg/hgrc
  $ echo a > a
  $ hg add a
  $ hg commit -m 'test'
  $ echo aaaaa > a
  $ hg commit -m 'largefile'
  $ hg debugdata .hg/store/data/a.i 1 # verify this is no the file content but includes "oid", the LFS "pointer".
  version https://git-lfs.github.com/spec/v1
  oid sha256:bdc26931acfb734b142a8d675f205becf27560dc461f501822de13274fe6fc8a
  size 6
  x-is-binary 0
  $ cd ..
  $ hg --config 'lfs.url=https://dewey-lfs.vip.facebook.com/lfs' clone test test2
  updating to branch default
  abort: LFS server error. Remote object for file data/a.i not found:(.*)! (re)
  [255]