( )⚙ D1392 bundle2: inline changegroup.readexactly()

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Differential D1392

bundle2: inline changegroup.readexactly()
ClosedPublic

Authored by indygreg on Nov 14 2017, 1:26 AM.

Details

Reviewers
durin42
Group Reviewers
hg-reviewers
Commits
rHG1fb0846ad792: bundle2: inline changegroup.readexactly()
Summary

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)

Diff Detail

Repository
rHG Mercurial
Lint
Lint Skipped
Unit
Unit Tests Skipped

Event Timeline

indygreg created this revision.Nov 14 2017, 1:26 AM
durin42 accepted this revision.Nov 20 2017, 6:42 PM
This revision is now accepted and ready to land.Nov 20 2017, 6:42 PM
Closed by commit rHG1fb0846ad792: bundle2: inline changegroup.readexactly() (authored by indygreg). · Explain WhyNov 20 2017, 6:50 PM
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

PathPackages
Mmercurial/bundle2.py (18 lines)

Diff 3470

mercurial/bundle2.py

Part payload data consists of framed chunks. This function takes Part payload data consists of framed chunks. This function takes
a file handle and emits those chunks. a file handle and emits those chunks.
""" """
dolog = ui.configbool('devel', 'bundle2.debug') dolog = ui.configbool('devel', 'bundle2.debug')
debug = ui.debug debug = ui.debug
headersize = struct.calcsize(_fpayloadsize) headersize = struct.calcsize(_fpayloadsize)
readexactly = changegroup.readexactly readexactly = changegroup.readexactly
read = fh.read
chunksize = _unpack(_fpayloadsize, readexactly(fh, headersize))[0] chunksize = _unpack(_fpayloadsize, readexactly(fh, headersize))[0]
indebug(ui, 'payload chunk size: %i' % chunksize) indebug(ui, 'payload chunk size: %i' % chunksize)
# changegroup.readexactly() is inlined below for performance.
while chunksize: while chunksize:
if chunksize >= 0: if chunksize >= 0:
yield readexactly(fh, chunksize) s = read(chunksize)
if len(s) < chunksize:
raise error.Abort(_('stream ended unexpectedly '
' (got %d bytes, expected %d)') %
(len(s), chunksize))
yield s
elif chunksize == flaginterrupt: elif chunksize == flaginterrupt:
# Interrupt "signal" detected. The regular stream is interrupted # Interrupt "signal" detected. The regular stream is interrupted
# and a bundle2 part follows. Consume it. # and a bundle2 part follows. Consume it.
interrupthandler(ui, fh)() interrupthandler(ui, fh)()
else: else:
raise error.BundleValueError( raise error.BundleValueError(
'negative payload chunk size: %s' % chunksize) 'negative payload chunk size: %s' % chunksize)
chunksize = _unpack(_fpayloadsize, readexactly(fh, headersize))[0] s = read(headersize)
if len(s) < headersize:
raise error.Abort(_('stream ended unexpectedly '
' (got %d bytes, expected %d)') %
(len(s), chunksize))
chunksize = _unpack(_fpayloadsize, s)[0]
# indebug() inlined for performance. # indebug() inlined for performance.
if dolog: if dolog:
debug('bundle2-input: payload chunk size: %i\n' % chunksize) debug('bundle2-input: payload chunk size: %i\n' % chunksize)
class unbundlepart(unpackermixin): class unbundlepart(unpackermixin):
"""a bundle part read from a bundle""" """a bundle part read from a bundle"""