contrib/perf.py

hgweb: send proper HTTP response after uncaught exception

This patch fixes a bug where hgweb would send an incomplete HTTP
response.

If an uncaught exception is raised when hgweb is processing a request,
hgweb attempts to send a generic error response and log that exception.

The server defaults to chunked transfer coding. If an uncaught exception
occurred, it was sending the error response string / chunk properly.
However, RFC 7230 Section 4.1 mandates a 0 size last chunk be sent to
indicate end of the entity body. hgweb was failing to send this last
chunk. As a result, properly written HTTP clients would assume more data
was coming and they would likely time out waiting for another chunk to
arrive.

Mercurial's own test harness was paving over the improper HTTP behavior
by not attempting to read the response body if the status code was 500.
This incorrect workaround was added in ba6577a19656 and has been removed
with this patch.

# perf.py - performance test routines
'''helper extension to measure performance'''

from mercurial import cmdutil, scmutil, util, commands, obsolete
from mercurial import repoview, branchmap, merge, copies
import time, os, sys

cmdtable = {}
command = cmdutil.command(cmdtable)

def timer(func, title=None):
    results = []
    begin = time.time()
    count = 0
    while True:
        ostart = os.times()
        cstart = time.time()
        r = func()
        cstop = time.time()
        ostop = os.times()
        count += 1
        a, b = ostart, ostop
        results.append((cstop - cstart, b[0] - a[0], b[1]-a[1]))
        if cstop - begin > 3 and count >= 100:
            break
        if cstop - begin > 10 and count >= 3:
            break
    if title:
        sys.stderr.write("! %s\n" % title)
    if r:
        sys.stderr.write("! result: %s\n" % r)
    m = min(results)
    sys.stderr.write("! wall %f comb %f user %f sys %f (best of %d)\n"
                     % (m[0], m[1] + m[2], m[1], m[2], count))

@command('perfwalk')
def perfwalk(ui, repo, *pats):
    try:
        m = scmutil.match(repo[None], pats, {})
        timer(lambda: len(list(repo.dirstate.walk(m, [], True, False))))
    except Exception:
        try:
            m = scmutil.match(repo[None], pats, {})
            timer(lambda: len([b for a, b, c in repo.dirstate.statwalk([], m)]))
        except Exception:
            timer(lambda: len(list(cmdutil.walk(repo, pats, {}))))

@command('perfannotate')
def perfannotate(ui, repo, f):
    fc = repo['.'][f]
    timer(lambda: len(fc.annotate(True)))

@command('perfstatus',
         [('u', 'unknown', False,
           'ask status to look for unknown files')])
def perfstatus(ui, repo, **opts):
    #m = match.always(repo.root, repo.getcwd())
    #timer(lambda: sum(map(len, repo.dirstate.status(m, [], False, False,
    #                                                False))))
    timer(lambda: sum(map(len, repo.status(**opts))))

@command('perfaddremove')
def perfaddremove(ui, repo):
    try:
        oldquiet = repo.ui.quiet
        repo.ui.quiet = True
        timer(lambda: scmutil.addremove(repo, dry_run=True))
    finally:
        repo.ui.quiet = oldquiet

def clearcaches(cl):
    # behave somewhat consistently across internal API changes
    if util.safehasattr(cl, 'clearcaches'):
        cl.clearcaches()
    elif util.safehasattr(cl, '_nodecache'):
        from mercurial.node import nullid, nullrev
        cl._nodecache = {nullid: nullrev}
        cl._nodepos = None

@command('perfheads')
def perfheads(ui, repo):
    cl = repo.changelog
    def d():
        len(cl.headrevs())
        clearcaches(cl)
    timer(d)

@command('perftags')
def perftags(ui, repo):
    import mercurial.changelog
    import mercurial.manifest
    def t():
        repo.changelog = mercurial.changelog.changelog(repo.sopener)
        repo.manifest = mercurial.manifest.manifest(repo.sopener)
        repo._tags = None
        return len(repo.tags())
    timer(t)

@command('perfancestors')
def perfancestors(ui, repo):
    heads = repo.changelog.headrevs()
    def d():
        for a in repo.changelog.ancestors(heads):
            pass
    timer(d)

@command('perfancestorset')
def perfancestorset(ui, repo, revset):
    revs = repo.revs(revset)
    heads = repo.changelog.headrevs()
    def d():
        s = repo.changelog.ancestors(heads)
        for rev in revs:
            rev in s
    timer(d)

@command('perfdirs')
def perfdirs(ui, repo):
    dirstate = repo.dirstate
    'a' in dirstate
    def d():
        dirstate.dirs()
        del dirstate._dirs
    timer(d)

@command('perfdirstate')
def perfdirstate(ui, repo):
    "a" in repo.dirstate
    def d():
        repo.dirstate.invalidate()
        "a" in repo.dirstate
    timer(d)

@command('perfdirstatedirs')
def perfdirstatedirs(ui, repo):
    "a" in repo.dirstate
    def d():
        "a" in repo.dirstate._dirs
        del repo.dirstate._dirs
    timer(d)

@command('perfdirstatefoldmap')
def perffoldmap(ui, repo):
    dirstate = repo.dirstate
    'a' in dirstate
    def d():
        dirstate._foldmap.get('a')
        del dirstate._foldmap
        del dirstate._dirs
    timer(d)

@command('perfdirstatewrite')
def perfdirstatewrite(ui, repo):
    ds = repo.dirstate
    "a" in ds
    def d():
        ds._dirty = True
        ds.write()
    timer(d)

@command('perfmergecalculate',
         [('r', 'rev', '.', 'rev to merge against')])
def perfmergecalculate(ui, repo, rev):
    wctx = repo[None]
    rctx = scmutil.revsingle(repo, rev, rev)
    ancestor = wctx.ancestor(rctx)
    # we don't want working dir files to be stat'd in the benchmark, so prime
    # that cache
    wctx.dirty()
    def d():
        # acceptremote is True because we don't want prompts in the middle of
        # our benchmark
        merge.calculateupdates(repo, wctx, rctx, ancestor, False, False, False,
                               acceptremote=True)
    timer(d)

@command('perfpathcopies', [], "REV REV")
def perfpathcopies(ui, repo, rev1, rev2):
    ctx1 = scmutil.revsingle(repo, rev1, rev1)
    ctx2 = scmutil.revsingle(repo, rev2, rev2)
    def d():
        copies.pathcopies(ctx1, ctx2)
    timer(d)

@command('perfmanifest', [], 'REV')
def perfmanifest(ui, repo, rev):
    ctx = scmutil.revsingle(repo, rev, rev)
    t = ctx.manifestnode()
    def d():
        repo.manifest._mancache.clear()
        repo.manifest._cache = None
        repo.manifest.read(t)
    timer(d)

@command('perfchangeset')
def perfchangeset(ui, repo, rev):
    n = repo[rev].node()
    def d():
        repo.changelog.read(n)
        #repo.changelog._cache = None
    timer(d)

@command('perfindex')
def perfindex(ui, repo):
    import mercurial.revlog
    mercurial.revlog._prereadsize = 2**24 # disable lazy parser in old hg
    n = repo["tip"].node()
    def d():
        cl = mercurial.revlog.revlog(repo.sopener, "00changelog.i")
        cl.rev(n)
    timer(d)

@command('perfstartup')
def perfstartup(ui, repo):
    cmd = sys.argv[0]
    def d():
        os.system("HGRCPATH= %s version -q > /dev/null" % cmd)
    timer(d)

@command('perfparents')
def perfparents(ui, repo):
    nl = [repo.changelog.node(i) for i in xrange(1000)]
    def d():
        for n in nl:
            repo.changelog.parents(n)
    timer(d)

@command('perflookup')
def perflookup(ui, repo, rev):
    timer(lambda: len(repo.lookup(rev)))

@command('perfrevrange')
def perfrevrange(ui, repo, *specs):
    revrange = scmutil.revrange
    timer(lambda: len(revrange(repo, specs)))

@command('perfnodelookup')
def perfnodelookup(ui, repo, rev):
    import mercurial.revlog
    mercurial.revlog._prereadsize = 2**24 # disable lazy parser in old hg
    n = repo[rev].node()
    cl = mercurial.revlog.revlog(repo.sopener, "00changelog.i")
    def d():
        cl.rev(n)
        clearcaches(cl)
    timer(d)

@command('perflog',
         [('', 'rename', False, 'ask log to follow renames')])
def perflog(ui, repo, **opts):
    ui.pushbuffer()
    timer(lambda: commands.log(ui, repo, rev=[], date='', user='',
                               copies=opts.get('rename')))
    ui.popbuffer()

@command('perfmoonwalk')
def perfmoonwalk(ui, repo):
    """benchmark walking the changelog backwards

    This also loads the changelog data for each revision in the changelog.
    """
    def moonwalk():
        for i in xrange(len(repo), -1, -1):
            ctx = repo[i]
            ctx.branch() # read changelog data (in addition to the index)
    timer(moonwalk)

@command('perftemplating')
def perftemplating(ui, repo):
    ui.pushbuffer()
    timer(lambda: commands.log(ui, repo, rev=[], date='', user='',
                               template='{date|shortdate} [{rev}:{node|short}]'
                               ' {author|person}: {desc|firstline}\n'))
    ui.popbuffer()

@command('perfcca')
def perfcca(ui, repo):
    timer(lambda: scmutil.casecollisionauditor(ui, False, repo.dirstate))

@command('perffncacheload')
def perffncacheload(ui, repo):
    s = repo.store
    def d():
        s.fncache._load()
    timer(d)

@command('perffncachewrite')
def perffncachewrite(ui, repo):
    s = repo.store
    s.fncache._load()
    def d():
        s.fncache._dirty = True
        s.fncache.write()
    timer(d)

@command('perffncacheencode')
def perffncacheencode(ui, repo):
    s = repo.store
    s.fncache._load()
    def d():
        for p in s.fncache.entries:
            s.encode(p)
    timer(d)

@command('perfdiffwd')
def perfdiffwd(ui, repo):
    """Profile diff of working directory changes"""
    options = {
        'w': 'ignore_all_space',
        'b': 'ignore_space_change',
        'B': 'ignore_blank_lines',
        }

    for diffopt in ('', 'w', 'b', 'B', 'wB'):
        opts = dict((options[c], '1') for c in diffopt)
        def d():
            ui.pushbuffer()
            commands.diff(ui, repo, **opts)
            ui.popbuffer()
        title = 'diffopts: %s' % (diffopt and ('-' + diffopt) or 'none')
        timer(d, title)

@command('perfrevlog',
         [('d', 'dist', 100, 'distance between the revisions')],
         "[INDEXFILE]")
def perfrevlog(ui, repo, file_, **opts):
    from mercurial import revlog
    dist = opts['dist']
    def d():
        r = revlog.revlog(lambda fn: open(fn, 'rb'), file_)
        for x in xrange(0, len(r), dist):
            r.revision(r.node(x))

    timer(d)

@command('perfrevset',
         [('C', 'clear', False, 'clear volatile cache between each call.')],
         "REVSET")
def perfrevset(ui, repo, expr, clear=False):
    """benchmark the execution time of a revset

    Use the --clean option if need to evaluate the impact of build volatile
    revisions set cache on the revset execution. Volatile cache hold filtered
    and obsolete related cache."""
    def d():
        if clear:
            repo.invalidatevolatilesets()
        for r in repo.revs(expr): pass
    timer(d)

@command('perfvolatilesets')
def perfvolatilesets(ui, repo, *names):
    """benchmark the computation of various volatile set

    Volatile set computes element related to filtering and obsolescence."""
    repo = repo.unfiltered()

    def getobs(name):
        def d():
            repo.invalidatevolatilesets()
            obsolete.getrevs(repo, name)
        return d

    allobs = sorted(obsolete.cachefuncs)
    if names:
        allobs = [n for n in allobs if n in names]

    for name in allobs:
        timer(getobs(name), title=name)

    def getfiltered(name):
        def d():
            repo.invalidatevolatilesets()
            repoview.filterrevs(repo, name)
        return d

    allfilter = sorted(repoview.filtertable)
    if names:
        allfilter = [n for n in allfilter if n in names]

    for name in allfilter:
        timer(getfiltered(name), title=name)

@command('perfbranchmap',
         [('f', 'full', False,
           'Includes build time of subset'),
         ])
def perfbranchmap(ui, repo, full=False):
    """benchmark the update of a branchmap

    This benchmarks the full repo.branchmap() call with read and write disabled
    """
    def getbranchmap(filtername):
        """generate a benchmark function for the filtername"""
        if filtername is None:
            view = repo
        else:
            view = repo.filtered(filtername)
        def d():
            if full:
                view._branchcaches.clear()
            else:
                view._branchcaches.pop(filtername, None)
            view.branchmap()
        return d
    # add filter in smaller subset to bigger subset
    possiblefilters = set(repoview.filtertable)
    allfilters = []
    while possiblefilters:
        for name in possiblefilters:
            subset = branchmap.subsettable.get(name)
            if subset not in possiblefilters:
                break
        else:
            assert False, 'subset cycle %s!' % possiblefilters
        allfilters.append(name)
        possiblefilters.remove(name)

    # warm the cache
    if not full:
        for name in allfilters:
            repo.filtered(name).branchmap()
    # add unfiltered
    allfilters.append(None)
    oldread = branchmap.read
    oldwrite = branchmap.branchcache.write
    try:
        branchmap.read = lambda repo: None
        branchmap.write = lambda repo: None
        for name in allfilters:
            timer(getbranchmap(name), title=str(name))
    finally:
        branchmap.read = oldread
        branchmap.branchcache.write = oldwrite