bdiff: don't check border condition in loop
This is pretty much a copy of d500ddae7494, just to a different loop.
The condition `p == plast` (`plast == a + len - 1`) was only true on
the final iteration of the loop. So it was wasteful to check for it
on every iteration. We decrease the iteration count by 1 and add an
explicit check for `p == plast` after the loop.
Again, we see modest wins.
From the mozilla-unified repository:
$ perfbdiff -m 3041e4d59df2
! wall 0.035502 comb 0.040000 user 0.040000 sys 0.000000 (best of 100)
! wall 0.030480 comb 0.030000 user 0.030000 sys 0.000000 (best of 100)
$ perfbdiff 0e9928989e9c --alldata --count 100
! wall 4.097394 comb 4.100000 user 4.100000 sys 0.000000 (best of 3)
! wall 3.597798 comb 3.600000 user 3.600000 sys 0.000000 (best of 3)
The 2nd example throws a total of ~3.3GB of data at bdiff. This
change increases the throughput from ~811 MB/s to ~924 MB/s.
# sshserver.py - ssh protocol server support for mercurial
#
# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import os
import sys
from .i18n import _
from . import (
error,
hook,
util,
wireproto,
)
class sshserver(wireproto.abstractserverproto):
def __init__(self, ui, repo):
self.ui = ui
self.repo = repo
self.lock = None
self.fin = ui.fin
self.fout = ui.fout
hook.redirect(True)
ui.fout = repo.ui.fout = ui.ferr
# Prevent insertion/deletion of CRs
util.setbinary(self.fin)
util.setbinary(self.fout)
def getargs(self, args):
data = {}
keys = args.split()
for n in xrange(len(keys)):
argline = self.fin.readline()[:-1]
arg, l = argline.split()
if arg not in keys:
raise error.Abort(_("unexpected parameter %r") % arg)
if arg == '*':
star = {}
for k in xrange(int(l)):
argline = self.fin.readline()[:-1]
arg, l = argline.split()
val = self.fin.read(int(l))
star[arg] = val
data['*'] = star
else:
val = self.fin.read(int(l))
data[arg] = val
return [data[k] for k in keys]
def getarg(self, name):
return self.getargs(name)[0]
def getfile(self, fpout):
self.sendresponse('')
count = int(self.fin.readline())
while count:
fpout.write(self.fin.read(count))
count = int(self.fin.readline())
def redirect(self):
pass
def groupchunks(self, fh):
return iter(lambda: fh.read(4096), '')
def compresschunks(self, chunks):
for chunk in chunks:
yield chunk
def sendresponse(self, v):
self.fout.write("%d\n" % len(v))
self.fout.write(v)
self.fout.flush()
def sendstream(self, source):
write = self.fout.write
for chunk in source.gen:
write(chunk)
self.fout.flush()
def sendpushresponse(self, rsp):
self.sendresponse('')
self.sendresponse(str(rsp.res))
def sendpusherror(self, rsp):
self.sendresponse(rsp.res)
def sendooberror(self, rsp):
self.ui.ferr.write('%s\n-\n' % rsp.message)
self.ui.ferr.flush()
self.fout.write('\n')
self.fout.flush()
def serve_forever(self):
try:
while self.serve_one():
pass
finally:
if self.lock is not None:
self.lock.release()
sys.exit(0)
handlers = {
str: sendresponse,
wireproto.streamres: sendstream,
wireproto.pushres: sendpushresponse,
wireproto.pusherr: sendpusherror,
wireproto.ooberror: sendooberror,
}
def serve_one(self):
cmd = self.fin.readline()[:-1]
if cmd and cmd in wireproto.commands:
rsp = wireproto.dispatch(self.repo, self, cmd)
self.handlers[rsp.__class__](self, rsp)
elif cmd:
impl = getattr(self, 'do_' + cmd, None)
if impl:
r = impl()
if r is not None:
self.sendresponse(r)
else: self.sendresponse("")
return cmd != ''
def _client(self):
client = os.environ.get('SSH_CLIENT', '').split(' ', 1)[0]
return 'remote:ssh:' + client