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Differential D6156

branchcache: add attributes to track which nodes are verified
ClosedPublic

Authored by pulkit on Mar 19 2019, 9:40 AM.

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rHG111de135fc76: branchcache: add attributes to track which nodes are verified
Summary

Half of the cost of loading branchcache comes from verifiying all the nodes it
has. We don't need to verify all the nodes in all the cases. Sometimes we need
to verify only a set of nodes for a set of branches. We can ignore nodes of
other branches as we are not going to read them.

This patch introduces two attributes to branchcache class. _verifiedbranches is
a set which will tell the branches for which it's head nodes are verified.
_closedverified is a boolean which will tell whether all closednodes are
verified or not.

Another idea which I had was to keep a set of nodes which are verified, but it
will be more ugly and difficult to track things on node level.

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rHG Mercurial
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Event Timeline

pulkit created this revision.Mar 19 2019, 9:40 AM
Closed by commit rHG111de135fc76: branchcache: add attributes to track which nodes are verified (authored by pulkit). · Explain WhyMar 23 2019, 11:42 AM
This revision was automatically updated to reflect the committed changes.
yuja added a subscriber: yuja.Mar 23 2019, 9:26 PM

@@ -231,8 +235,10 @@

    raise ValueError(
        r'node %s does not exist' % pycompat.sysstr(hex(node)))
self._entries.setdefault(label, []).append(node)

+ self._verifiedbranches.add(label)

Can we expect that we'll rewrite this load() logic to handle verification
state of multiple nodes (i.e. heads) correctly? It's unclear to me how lazy
verification will be implemented.

Revision Contents
Changeset List

PathPackages
Mmercurial/branchmap.py (6 lines)

Diff 14560

mercurial/branchmap.py

# closednodes is a set of nodes that close their branch. If the branch # closednodes is a set of nodes that close their branch. If the branch
# cache has been updated, it may contain nodes that are no longer # cache has been updated, it may contain nodes that are no longer
# heads. # heads.
if closednodes is None: if closednodes is None:
self._closednodes = set() self._closednodes = set()
else: else:
self._closednodes = closednodes self._closednodes = closednodes
self._entries = dict(entries) self._entries = dict(entries)
# whether closed nodes are verified or not
self._closedverified = False
# branches for which nodes are verified
self._verifiedbranches = set()
def __iter__(self): def __iter__(self):
return iter(self._entries) return iter(self._entries)
def __setitem__(self, key, value): def __setitem__(self, key, value):
self._entries[key] = value self._entries[key] = value
def __getitem__(self, key): def __getitem__(self, key):
if state not in 'oc': if state not in 'oc':
raise ValueError(r'invalid branch state') raise ValueError(r'invalid branch state')
label = encoding.tolocal(label.strip()) label = encoding.tolocal(label.strip())
node = bin(node) node = bin(node)
if not cl.hasnode(node): if not cl.hasnode(node):
raise ValueError( raise ValueError(
r'node %s does not exist' % pycompat.sysstr(hex(node))) r'node %s does not exist' % pycompat.sysstr(hex(node)))
self._entries.setdefault(label, []).append(node) self._entries.setdefault(label, []).append(node)
self._verifiedbranches.add(label)
if state == 'c': if state == 'c':
self._closednodes.add(node) self._closednodes.add(node)
self._closedverified = True
@staticmethod @staticmethod
def _filename(repo): def _filename(repo):
"""name of a branchcache file for a given repo or repoview""" """name of a branchcache file for a given repo or repoview"""
filename = "branch2" filename = "branch2"
if repo.filtername: if repo.filtername:
filename = '%s-%s' % (filename, repo.filtername) filename = '%s-%s' % (filename, repo.filtername)
return filename return filename