nodemap: add a (python) index class for persistent nodemap testing
Using the persistent nodemap require a compeling performance boost and an
existing implementation. The benefit of the persistent nodemap for pure python
code is unclear and we don't have a C implementation for it. Yet we would like
to actually start testing it in more details and define an API for using that
persistent nodemap.
We introduce a new `devel` config option to use an index class dedicated to
Nodemap Testing. This feature is "pure" only because having using a pure-python
index with the `cext` policy proved more difficult than I would like.
There is nothing going on in that class for now, but the coming changeset will
change that.
Differential Revision: https://phab.mercurial-scm.org/D7840
--- a/mercurial/configitems.py Wed Jan 15 15:47:59 2020 +0100
+++ b/mercurial/configitems.py Wed Jan 15 15:48:09 2020 +0100
@@ -406,6 +406,9 @@
b'devel', b'legacy.exchange', default=list,
)
coreconfigitem(
+ b'devel', b'persistent-nodemap', default=False,
+)
+coreconfigitem(
b'devel', b'servercafile', default=b'',
)
coreconfigitem(
--- a/mercurial/localrepo.py Wed Jan 15 15:47:59 2020 +0100
+++ b/mercurial/localrepo.py Wed Jan 15 15:48:09 2020 +0100
@@ -934,6 +934,8 @@
options[b'rust.index'] = True
if ui.configbool(b'experimental', b'exp-persistent-nodemap'):
options[b'exp-persistent-nodemap'] = True
+ if ui.configbool(b'devel', b'persistent-nodemap'):
+ options[b'devel-force-nodemap'] = True
return options
--- a/mercurial/pure/parsers.py Wed Jan 15 15:47:59 2020 +0100
+++ b/mercurial/pure/parsers.py Wed Jan 15 15:48:09 2020 +0100
@@ -141,6 +141,15 @@
self._extra = self._extra[: i - self._lgt]
+class PersistentNodeMapIndexObject(IndexObject):
+ """a Debug oriented class to test persistent nodemap
+
+ We need a simple python object to test API and higher level behavior. See
+ the Rust implementation for more serious usage. This should be used only
+ through the dedicated `devel.persistent-nodemap` config.
+ """
+
+
class InlinedIndexObject(BaseIndexObject):
def __init__(self, data, inline=0):
self._data = data
@@ -188,6 +197,12 @@
return InlinedIndexObject(data, inline), (0, data)
+def parse_index_devel_nodemap(data, inline):
+ """like parse_index2, but alway return a PersistentNodeMapIndexObject
+ """
+ return PersistentNodeMapIndexObject(data), None
+
+
def parse_dirstate(dmap, copymap, st):
parents = [st[:20], st[20:40]]
# dereference fields so they will be local in loop
--- a/mercurial/revlog.py Wed Jan 15 15:47:59 2020 +0100
+++ b/mercurial/revlog.py Wed Jan 15 15:48:09 2020 +0100
@@ -352,6 +352,21 @@
return p
+NodemapRevlogIO = None
+
+if util.safehasattr(parsers, 'parse_index_devel_nodemap'):
+
+ class NodemapRevlogIO(revlogio):
+ """A debug oriented IO class that return a PersistentNodeMapIndexObject
+
+ The PersistentNodeMapIndexObject object is meant to test the persistent nodemap feature.
+ """
+
+ def parseindex(self, data, inline):
+ index, cache = parsers.parse_index_devel_nodemap(data, inline)
+ return index, cache
+
+
class rustrevlogio(revlogio):
def parseindex(self, data, inline):
index, cache = super(rustrevlogio, self).parseindex(data, inline)
@@ -596,9 +611,17 @@
self._storedeltachains = True
+ devel_nodemap = (
+ self.nodemap_file
+ and opts.get(b'devel-force-nodemap', False)
+ and NodemapRevlogIO is not None
+ )
+
self._io = revlogio()
if self.version == REVLOGV0:
self._io = revlogoldio()
+ elif devel_nodemap:
+ self._io = NodemapRevlogIO()
elif rustrevlog is not None and self.opener.options.get(b'rust.index'):
self._io = rustrevlogio()
try:
--- a/tests/test-persistent-nodemap.t Wed Jan 15 15:47:59 2020 +0100
+++ b/tests/test-persistent-nodemap.t Wed Jan 15 15:48:09 2020 +0100
@@ -8,6 +8,8 @@
$ cat << EOF >> .hg/hgrc
> [experimental]
> exp-persistent-nodemap=yes
+ > [devel]
+ > persistent-nodemap=yes
> EOF
$ hg debugbuilddag .+5000
$ f --size .hg/store/00changelog.n