[Unison-hackers] [unison-svn] r375 - trunk/src

[vouillon@seas.upenn.edu]

Author: vouillon
Date: 2009-07-16 18:13:45 -0400 (Thu, 16 Jul 2009)
New Revision: 375

Modified:
   trunk/src/RECENTNEWS
   trunk/src/mkProjectInfo.ml
   trunk/src/update.ml
Log:
* Fixed small bug in new update detection optimization:
  do not perform the optimization for directories with ignored
  children in the archive.  Indeed, we cannot rely on the archive in
  this case instead of reading the directory contents from the
  filesystem (systematically pruning the ignored children from the
  archive is too costly).


Modified: trunk/src/RECENTNEWS
===================================================================
--- trunk/src/RECENTNEWS	2009-07-16 19:33:15 UTC (rev 374)
+++ trunk/src/RECENTNEWS	2009-07-16 22:13:45 UTC (rev 375)
@@ -1,5 +1,15 @@
 CHANGES FROM VERSION 2.36.-27
 
+* Fixed small bug in new update detection optimization:
+  do not perform the optimization for directories with ignored
+  children in the archive.  Indeed, we cannot rely on the archive in
+  this case instead of reading the directory contents from the
+  filesystem (systematically pruning the ignored children from the
+  archive is too costly).
+
+-------------------------------
+CHANGES FROM VERSION 2.36.-27
+
 * Experimental update detection optimization:
   do not read the contents of unchanged directories
 * MyMap.map and MyMap.mapi now iterate in increasing order

Modified: trunk/src/mkProjectInfo.ml
===================================================================
--- trunk/src/mkProjectInfo.ml	2009-07-16 19:33:15 UTC (rev 374)
+++ trunk/src/mkProjectInfo.ml	2009-07-16 22:13:45 UTC (rev 375)
@@ -93,3 +93,4 @@
 
 
 
+

Modified: trunk/src/update.ml
===================================================================
--- trunk/src/update.ml	2009-07-16 19:33:15 UTC (rev 374)
+++ trunk/src/update.ml	2009-07-16 22:13:45 UTC (rev 375)
@@ -1316,7 +1316,8 @@
    whether the directory is now empty *)
 let rec buildUpdateChildren
     fspath path (archChi: archive NameMap.t) unchangedChildren fastCheckInfos
-    : archive NameMap.t option * (Name.t * Common.updateItem) list * bool
+    : archive NameMap.t option * (Name.t * Common.updateItem) list *
+      bool * bool
     =
   showStatusDir path;
   let skip =
@@ -1334,7 +1335,7 @@
              | _ ->
                  ())
           archChi;
-      (None, [], false)
+      (None, [], false, false)
     end else begin
       let updates = ref [] in
       let archUpdated = ref false in
@@ -1352,16 +1353,18 @@
       let newChi = NameMap.mapi handleChild archChi in
       (* The Recon module relies on the updates to be sorted *)
       ((if !archUpdated then Some newChi else None),
-       Safelist.rev !updates, false)
+       Safelist.rev !updates, false, false)
     end
   end else
   let curChildren = ref (getChildren fspath path) in
   let emptied = not (NameMap.is_empty archChi) && !curChildren = [] in
+  let hasIgnoredChildren = ref false in
   let updates = ref [] in
   let archUpdated = ref false in
   let handleChild nm archive status =
     let path' = Path.child path nm in
     if Globals.shouldIgnore path' then begin
+      hasIgnoredChildren := true;
       debugignore (fun()->Util.msg "buildUpdateChildren: ignoring path %s\n"
                             (Path.toString path'));
       archive
@@ -1440,7 +1443,7 @@
     !curChildren;
   (* The Recon module relies on the updates to be sorted *)
   ((if !archUpdated then Some newChi else None),
-   Safelist.rev !updates, emptied)
+   Safelist.rev !updates, emptied, !hasIgnoredChildren)
 
 and buildUpdateRec archive currfspath path fastCheckInfos =
   try
@@ -1497,10 +1500,20 @@
             (PropsUpdated, info.Fileinfo.desc) in
         let unchanged =
           dirContentsClearlyUnchanged info archDesc fastCheckInfos in
-        let (newChildren, childUpdates, emptied) =
+        let (newChildren, childUpdates, emptied, hasIgnoredChildren) =
           buildUpdateChildren
             currfspath path prevChildren unchanged fastCheckInfos in
         let (archDesc, updated) =
+          (* If the archive contain ignored children, we cannot use it to
+             skip reading the directory contents from the filesystem.
+             Actually, we could check for ignored children in the archive,
+             but this has a significant cost.  We could mark directories
+             with ignored children, and only perform the checks for them,
+             but that does not seem worthwhile, are directories with
+             ignored children are expected to be rare in the archive.
+             (These are files or directories which used not to be
+             ignored and are now ignored.) *)
+          if hasIgnoredChildren then (archDesc, true) else
           directoryCheckContentUnchanged
             currfspath path info archDesc childUpdates fastCheckInfos in
         (begin match newChildren with
@@ -1517,7 +1530,7 @@
            NoUpdates)
     | (`DIRECTORY, _) ->
         debug (fun() -> Util.msg "  buildUpdate -> New directory\n");
-        let (newChildren, childUpdates, _) =
+        let (newChildren, childUpdates, _, _) =
           buildUpdateChildren
             currfspath path NameMap.empty false fastCheckInfos in
         (None,