bundle2: implement consume() API on unbundlepart
We want bundle parts to not be seekable by default. That means
eliminating the generic seek() method.
A common pattern in bundle2.py is to seek to the end of the part
data. This is mainly used by the part iteration code to ensure
the underlying stream is advanced to the next bundle part.
In this commit, we establish a dedicated API for consuming a
bundle2 part data. We switch users of seek() to it.
The old implementation of seek(0, os.SEEK_END) would effectively
call self.read(). The new implementation calls self.read(32768)
in a loop. The old implementation would therefore assemble a
buffer to hold all remaining data being seeked over. For seeking
over large bundle parts, this would involve a large allocation and
a lot of overhead to collect intermediate data! This overhead can
be seen in the results for `hg perfbundleread`:
! bundle2 iterparts()
! wall 10.891305 comb 10.820000 user 7.990000 sys 2.830000 (best of 3)
! wall 8.070791 comb 8.060000 user 7.180000 sys 0.880000 (best of 3)
! bundle2 part seek()
! wall 12.991478 comb 10.390000 user 7.720000 sys 2.670000 (best of 3)
! wall 10.370142 comb 10.350000 user 7.430000 sys 2.920000 (best of 3)
Of course, skipping over large payload data isn't likely very common.
So I doubt the performance wins will be observed in the wild.
Differential Revision: https://phab.mercurial-scm.org/D1388
Tests of 'hg status --rev <rev>' to make sure status between <rev> and '.' get
combined correctly with the dirstate status.
$ hg init
First commit
$ $PYTHON $TESTDIR/generate-working-copy-states.py state 2 1
$ hg addremove --similarity 0
adding content1_content1_content1-tracked
adding content1_content1_content1-untracked
adding content1_content1_content3-tracked
adding content1_content1_content3-untracked
adding content1_content1_missing-tracked
adding content1_content1_missing-untracked
adding content1_content2_content1-tracked
adding content1_content2_content1-untracked
adding content1_content2_content2-tracked
adding content1_content2_content2-untracked
adding content1_content2_content3-tracked
adding content1_content2_content3-untracked
adding content1_content2_missing-tracked
adding content1_content2_missing-untracked
adding content1_missing_content1-tracked
adding content1_missing_content1-untracked
adding content1_missing_content3-tracked
adding content1_missing_content3-untracked
adding content1_missing_missing-tracked
adding content1_missing_missing-untracked
$ hg commit -m first
Second commit
$ $PYTHON $TESTDIR/generate-working-copy-states.py state 2 2
$ hg addremove --similarity 0
removing content1_missing_content1-tracked
removing content1_missing_content1-untracked
removing content1_missing_content3-tracked
removing content1_missing_content3-untracked
removing content1_missing_missing-tracked
removing content1_missing_missing-untracked
adding missing_content2_content2-tracked
adding missing_content2_content2-untracked
adding missing_content2_content3-tracked
adding missing_content2_content3-untracked
adding missing_content2_missing-tracked
adding missing_content2_missing-untracked
$ hg commit -m second
Working copy
$ $PYTHON $TESTDIR/generate-working-copy-states.py state 2 wc
$ hg addremove --similarity 0
adding content1_missing_content1-tracked
adding content1_missing_content1-untracked
adding content1_missing_content3-tracked
adding content1_missing_content3-untracked
adding content1_missing_missing-tracked
adding content1_missing_missing-untracked
adding missing_missing_content3-tracked
adding missing_missing_content3-untracked
adding missing_missing_missing-tracked
adding missing_missing_missing-untracked
$ hg forget *_*_*-untracked
$ rm *_*_missing-*
Status compared to parent of the working copy, i.e. the dirstate status
$ hg status -A --rev 1 'glob:missing_content2_content3-tracked'
M missing_content2_content3-tracked
$ hg status -A --rev 1 'glob:missing_content2_content2-tracked'
C missing_content2_content2-tracked
$ hg status -A --rev 1 'glob:missing_missing_content3-tracked'
A missing_missing_content3-tracked
$ hg status -A --rev 1 'glob:missing_missing_content3-untracked'
? missing_missing_content3-untracked
$ hg status -A --rev 1 'glob:missing_content2_*-untracked'
R missing_content2_content2-untracked
R missing_content2_content3-untracked
R missing_content2_missing-untracked
$ hg status -A --rev 1 'glob:missing_*_missing-tracked'
! missing_content2_missing-tracked
! missing_missing_missing-tracked
$ hg status -A --rev 1 'glob:missing_missing_missing-untracked'
missing_missing_missing-untracked: The system cannot find the file specified (windows !)
missing_missing_missing-untracked: No such file or directory (no-windows !)
Status between first and second commit. Should ignore dirstate status.
$ hg status -A --rev 0:1 'glob:content1_content2_*'
M content1_content2_content1-tracked
M content1_content2_content1-untracked
M content1_content2_content2-tracked
M content1_content2_content2-untracked
M content1_content2_content3-tracked
M content1_content2_content3-untracked
M content1_content2_missing-tracked
M content1_content2_missing-untracked
$ hg status -A --rev 0:1 'glob:content1_content1_*'
C content1_content1_content1-tracked
C content1_content1_content1-untracked
C content1_content1_content3-tracked
C content1_content1_content3-untracked
C content1_content1_missing-tracked
C content1_content1_missing-untracked
$ hg status -A --rev 0:1 'glob:missing_content2_*'
A missing_content2_content2-tracked
A missing_content2_content2-untracked
A missing_content2_content3-tracked
A missing_content2_content3-untracked
A missing_content2_missing-tracked
A missing_content2_missing-untracked
$ hg status -A --rev 0:1 'glob:content1_missing_*'
R content1_missing_content1-tracked
R content1_missing_content1-untracked
R content1_missing_content3-tracked
R content1_missing_content3-untracked
R content1_missing_missing-tracked
R content1_missing_missing-untracked
$ hg status -A --rev 0:1 'glob:missing_missing_*'
Status compared to one revision back, checking that the dirstate status
is correctly combined with the inter-revision status
$ hg status -A --rev 0 'glob:content1_*_content[23]-tracked'
M content1_content1_content3-tracked
M content1_content2_content2-tracked
M content1_content2_content3-tracked
M content1_missing_content3-tracked
$ hg status -A --rev 0 'glob:content1_*_content1-tracked'
C content1_content1_content1-tracked
C content1_content2_content1-tracked
C content1_missing_content1-tracked
$ hg status -A --rev 0 'glob:missing_*_content?-tracked'
A missing_content2_content2-tracked
A missing_content2_content3-tracked
A missing_missing_content3-tracked
BROKEN: missing_content2_content[23]-untracked exist, so should be listed
$ hg status -A --rev 0 'glob:missing_*_content?-untracked'
? missing_missing_content3-untracked
$ hg status -A --rev 0 'glob:content1_*_*-untracked'
R content1_content1_content1-untracked
R content1_content1_content3-untracked
R content1_content1_missing-untracked
R content1_content2_content1-untracked
R content1_content2_content2-untracked
R content1_content2_content3-untracked
R content1_content2_missing-untracked
R content1_missing_content1-untracked
R content1_missing_content3-untracked
R content1_missing_missing-untracked
$ hg status -A --rev 0 'glob:*_*_missing-tracked'
! content1_content1_missing-tracked
! content1_content2_missing-tracked
! content1_missing_missing-tracked
! missing_content2_missing-tracked
! missing_missing_missing-tracked
$ hg status -A --rev 0 'glob:missing_*_missing-untracked'