contrib/benchmarks/perf.py

sparse-read: target density of 50% instead of 25%

The target density value is wrong. The default target chain span is
4*text-length. However, the target max chain payload is 2*text-length. So
default target density should be 50% (2/4) not 25% (1/4).

# perf.py - asv benchmarks using contrib/perf.py extension
#
# Copyright 2016 Logilab SA <[e-mail]>
#
# 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

from . import perfbench

@perfbench()
def track_tags(perf):
    return perf("perftags")

@perfbench()
def track_status(perf):
    return perf("perfstatus", unknown=False)

@perfbench(params=[('rev', ['1000', '10000', 'tip'])])
def track_manifest(perf, rev):
    return perf("perfmanifest", rev)

@perfbench()
def track_heads(perf):
    return perf("perfheads")