branchcache: skip entries that are topological heads in the on disk file
In the majority of cases, topological heads are also branch heads. We have
efficient way to get the topological heads and efficient way to retrieve
their branch information. So there is little value in putting them in the branch
cache file explicitly. On the contrary, writing them explicitly tend to create
very large cache file that are inefficient to read and update.
So the branch cache v3 format is no longer including them. This changeset focus
on the format aspect and have no focus on the performance aspect. We will cover
that later.
import os
from mercurial.hgweb import hgwebdir_mod
hgwebdir = hgwebdir_mod.hgwebdir
os.mkdir(b'webdir')
os.chdir(b'webdir')
webdir = os.path.realpath(b'.')
def trivial_response(req, res):
return []
def make_hgwebdir(gc_rate=None):
config = os.path.join(webdir, b'hgwebdir.conf')
with open(config, 'wb') as configfile:
configfile.write(b'[experimental]\n')
if gc_rate is not None:
configfile.write(b'web.full-garbage-collection-rate=%d\n' % gc_rate)
hg_wd = hgwebdir(config)
hg_wd._runwsgi = trivial_response
return hg_wd
def process_requests(webdir_instance, number):
# we don't care for now about passing realistic arguments
for _ in range(number):
for chunk in webdir_instance.run_wsgi(None, None):
pass
without_gc = make_hgwebdir(gc_rate=0)
process_requests(without_gc, 5)
assert without_gc.requests_count == 5
assert without_gc.gc_full_collections_done == 0
with_gc = make_hgwebdir(gc_rate=2)
process_requests(with_gc, 5)
assert with_gc.requests_count == 5
assert with_gc.gc_full_collections_done == 2
with_systematic_gc = make_hgwebdir() # default value of the setting
process_requests(with_systematic_gc, 3)
assert with_systematic_gc.requests_count == 3
assert with_systematic_gc.gc_full_collections_done == 3