revlog: move revision verification out of verify
authorGregory Szorc <gregory.szorc@gmail.com>
Mon, 24 Sep 2018 11:27:47 -0700
changeset 39877 733db72f0f54
parent 39876 01c0f01b562b
child 39878 2ac4f3e97813
revlog: move revision verification out of verify File revision verification is performing low-level checks of file storage, namely that flags are appropriate and revision data can be resolved. Since these checks are somewhat revlog-specific and may not be appropriate for alternate storage backends, this commit moves those checks from verify.py to revlog.py. Because we're now emitting warnings/errors that apply to specific revisions, we taught the iverifyproblem interface to expose the problematic node and to report this node in verify output. This was necessary to prevent unwanted test changes. After this change, revlog.verifyintegrity() and file verify code in verify.py both iterate over revisions and resolve their fulltext. But they do so in separate loops. (verify.py needs to resolve fulltexts as part of calling renamed() - at least when using revlogs.) This should add overhead. But on the mozilla-unified repo: $ hg verify before: time: real 700.640 secs (user 585.520+0.000 sys 23.480+0.000) after: time: real 682.380 secs (user 570.370+0.000 sys 22.240+0.000) I'm not sure what's going on. Maybe avoiding the filelog attribute proxies shaved off enough time to offset the losses? Maybe fulltext resolution has less overhead than I thought? I've left a comment indicating the potential for optimization. But because it doesn't produce a performance regression on a large repository, I'm not going to worry about it. Differential Revision: https://phab.mercurial-scm.org/D4745
mercurial/filelog.py
mercurial/repository.py
mercurial/revlog.py
mercurial/verify.py
--- a/mercurial/filelog.py	Wed Sep 26 12:06:44 2018 -0700
+++ b/mercurial/filelog.py	Mon Sep 24 11:27:47 2018 -0700
@@ -53,7 +53,7 @@
     def linkrev(self, rev):
         return self._revlog.linkrev(rev)
 
-    # Used by verify.
+    # Unused.
     def flags(self, rev):
         return self._revlog.flags(rev)
 
@@ -77,7 +77,7 @@
     def iscensored(self, rev):
         return self._revlog.iscensored(rev)
 
-    # Used by repo verify.
+    # Unused.
     def rawsize(self, rev):
         return self._revlog.rawsize(rev)
 
--- a/mercurial/repository.py	Wed Sep 26 12:06:44 2018 -0700
+++ b/mercurial/repository.py	Mon Sep 24 11:27:47 2018 -0700
@@ -341,6 +341,12 @@
     error = interfaceutil.Attribute(
         """Message indicating a fatal problem.""")
 
+    node = interfaceutil.Attribute(
+        """Revision encountering the problem.
+
+        ``None`` means the problem doesn't apply to a single revision.
+        """)
+
 class irevisiondelta(interfaceutil.Interface):
     """Represents a delta between one revision and another.
 
@@ -790,6 +796,10 @@
         used to communicate data between invocations of multiple storage
         primitives.
 
+        If individual revisions cannot have their revision content resolved,
+        the method is expected to set the ``skipread`` key to a set of nodes
+        that encountered problems.
+
         The method yields objects conforming to the ``iverifyproblem``
         interface.
         """
--- a/mercurial/revlog.py	Wed Sep 26 12:06:44 2018 -0700
+++ b/mercurial/revlog.py	Mon Sep 24 11:27:47 2018 -0700
@@ -29,6 +29,7 @@
     nullhex,
     nullid,
     nullrev,
+    short,
     wdirfilenodeids,
     wdirhex,
     wdirid,
@@ -260,6 +261,7 @@
 class revlogproblem(object):
     warning = attr.ib(default=None)
     error = attr.ib(default=None)
+    node = attr.ib(default=None)
 
 # index v0:
 #  4 bytes: offset
@@ -2644,6 +2646,89 @@
                 warning=_("warning: '%s' uses revlog format %d; expected %d") %
                         (self.indexfile, version, state['expectedversion']))
 
+        state['skipread'] = set()
+
+        for rev in self:
+            node = self.node(rev)
+
+            # Verify contents. 4 cases to care about:
+            #
+            #   common: the most common case
+            #   rename: with a rename
+            #   meta: file content starts with b'\1\n', the metadata
+            #         header defined in filelog.py, but without a rename
+            #   ext: content stored externally
+            #
+            # More formally, their differences are shown below:
+            #
+            #                       | common | rename | meta  | ext
+            #  -------------------------------------------------------
+            #   flags()             | 0      | 0      | 0     | not 0
+            #   renamed()           | False  | True   | False | ?
+            #   rawtext[0:2]=='\1\n'| False  | True   | True  | ?
+            #
+            # "rawtext" means the raw text stored in revlog data, which
+            # could be retrieved by "revision(rev, raw=True)". "text"
+            # mentioned below is "revision(rev, raw=False)".
+            #
+            # There are 3 different lengths stored physically:
+            #  1. L1: rawsize, stored in revlog index
+            #  2. L2: len(rawtext), stored in revlog data
+            #  3. L3: len(text), stored in revlog data if flags==0, or
+            #     possibly somewhere else if flags!=0
+            #
+            # L1 should be equal to L2. L3 could be different from them.
+            # "text" may or may not affect commit hash depending on flag
+            # processors (see revlog.addflagprocessor).
+            #
+            #              | common  | rename | meta  | ext
+            # -------------------------------------------------
+            #    rawsize() | L1      | L1     | L1    | L1
+            #       size() | L1      | L2-LM  | L1(*) | L1 (?)
+            # len(rawtext) | L2      | L2     | L2    | L2
+            #    len(text) | L2      | L2     | L2    | L3
+            #  len(read()) | L2      | L2-LM  | L2-LM | L3 (?)
+            #
+            # LM:  length of metadata, depending on rawtext
+            # (*): not ideal, see comment in filelog.size
+            # (?): could be "- len(meta)" if the resolved content has
+            #      rename metadata
+            #
+            # Checks needed to be done:
+            #  1. length check: L1 == L2, in all cases.
+            #  2. hash check: depending on flag processor, we may need to
+            #     use either "text" (external), or "rawtext" (in revlog).
+
+            try:
+                skipflags = state.get('skipflags', 0)
+                if skipflags:
+                    skipflags &= self.flags(rev)
+
+                if skipflags:
+                    state['skipread'].add(node)
+                else:
+                    # Side-effect: read content and verify hash.
+                    self.revision(node)
+
+                l1 = self.rawsize(rev)
+                l2 = len(self.revision(node, raw=True))
+
+                if l1 != l2:
+                    yield revlogproblem(
+                        error=_('unpacked size is %d, %d expected') % (l2, l1),
+                        node=node)
+
+            except error.CensoredNodeError:
+                if state['erroroncensored']:
+                    yield revlogproblem(error=_('censored file data'),
+                                        node=node)
+                    state['skipread'].add(node)
+            except Exception as e:
+                yield revlogproblem(
+                    error=_('unpacking %s: %s') % (short(node), e),
+                    node=node)
+                state['skipread'].add(node)
+
     def storageinfo(self, exclusivefiles=False, sharedfiles=False,
                     revisionscount=False, trackedsize=False,
                     storedsize=False):
--- a/mercurial/verify.py	Wed Sep 26 12:06:44 2018 -0700
+++ b/mercurial/verify.py	Mon Sep 24 11:27:47 2018 -0700
@@ -343,7 +343,10 @@
 
         state = {
             # TODO this assumes revlog storage for changelog.
-            'expectedversion': self.repo.changelog.version & 0xFFFF
+            'expectedversion': self.repo.changelog.version & 0xFFFF,
+            'skipflags': self.skipflags,
+            # experimental config: censor.policy
+            'erroroncensored': ui.config('censor', 'policy') == 'abort',
         }
 
         files = sorted(set(filenodes) | set(filelinkrevs))
@@ -381,18 +384,25 @@
             if not len(fl) and (self.havecl or self.havemf):
                 self.err(lr, _("empty or missing %s") % f)
             else:
+                # Guard against implementations not setting this.
+                state['skipread'] = set()
                 for problem in fl.verifyintegrity(state):
+                    if problem.node is not None:
+                        linkrev = fl.linkrev(fl.rev(problem.node))
+                    else:
+                        linkrev = None
+
                     if problem.warning:
                         self.warn(problem.warning)
                     elif problem.error:
-                        self.err(lr, problem.error, f)
+                        self.err(linkrev if linkrev is not None else lr,
+                                 problem.error, f)
                     else:
                         raise error.ProgrammingError(
                             'problem instance does not set warning or error '
                             'attribute: %s' % problem.msg)
 
             seen = {}
-            rp = None
             for i in fl:
                 revisions += 1
                 n = fl.node(i)
@@ -403,75 +413,15 @@
                     else:
                         del filenodes[f][n]
 
-                # Verify contents. 4 cases to care about:
-                #
-                #   common: the most common case
-                #   rename: with a rename
-                #   meta: file content starts with b'\1\n', the metadata
-                #         header defined in filelog.py, but without a rename
-                #   ext: content stored externally
-                #
-                # More formally, their differences are shown below:
-                #
-                #                       | common | rename | meta  | ext
-                #  -------------------------------------------------------
-                #   flags()             | 0      | 0      | 0     | not 0
-                #   renamed()           | False  | True   | False | ?
-                #   rawtext[0:2]=='\1\n'| False  | True   | True  | ?
-                #
-                # "rawtext" means the raw text stored in revlog data, which
-                # could be retrieved by "revision(rev, raw=True)". "text"
-                # mentioned below is "revision(rev, raw=False)".
-                #
-                # There are 3 different lengths stored physically:
-                #  1. L1: rawsize, stored in revlog index
-                #  2. L2: len(rawtext), stored in revlog data
-                #  3. L3: len(text), stored in revlog data if flags==0, or
-                #     possibly somewhere else if flags!=0
-                #
-                # L1 should be equal to L2. L3 could be different from them.
-                # "text" may or may not affect commit hash depending on flag
-                # processors (see revlog.addflagprocessor).
-                #
-                #              | common  | rename | meta  | ext
-                # -------------------------------------------------
-                #    rawsize() | L1      | L1     | L1    | L1
-                #       size() | L1      | L2-LM  | L1(*) | L1 (?)
-                # len(rawtext) | L2      | L2     | L2    | L2
-                #    len(text) | L2      | L2     | L2    | L3
-                #  len(read()) | L2      | L2-LM  | L2-LM | L3 (?)
-                #
-                # LM:  length of metadata, depending on rawtext
-                # (*): not ideal, see comment in filelog.size
-                # (?): could be "- len(meta)" if the resolved content has
-                #      rename metadata
-                #
-                # Checks needed to be done:
-                #  1. length check: L1 == L2, in all cases.
-                #  2. hash check: depending on flag processor, we may need to
-                #     use either "text" (external), or "rawtext" (in revlog).
-                try:
-                    skipflags = self.skipflags
-                    if skipflags:
-                        skipflags &= fl.flags(i)
-                    if not skipflags:
-                        fl.read(n) # side effect: read content and do checkhash
-                        rp = fl.renamed(n)
-                    # the "L1 == L2" check
-                    l1 = fl.rawsize(i)
-                    l2 = len(fl.revision(n, raw=True))
-                    if l1 != l2:
-                        self.err(lr, _("unpacked size is %s, %s expected") %
-                                 (l2, l1), f)
-                except error.CensoredNodeError:
-                    # experimental config: censor.policy
-                    if ui.config("censor", "policy") == "abort":
-                        self.err(lr, _("censored file data"), f)
-                except Exception as inst:
-                    self.exc(lr, _("unpacking %s") % short(n), inst, f)
+                if n in state['skipread']:
+                    continue
 
                 # check renames
                 try:
+                    # This requires resolving fulltext (at least on revlogs). We
+                    # may want ``verifyintegrity()`` to pass a set of nodes with
+                    # rename metadata as an optimization.
+                    rp = fl.renamed(n)
                     if rp:
                         if lr is not None and ui.verbose:
                             ctx = lrugetctx(lr)