Merge pull request #39 from synopse/main

abouchez/mormot: noticeable performance boost

Author: gcarreno

entries/abouchez/src/brcmormot.lpr

@@ -34,27 +34,32 @@
     Min, Max: SmallInt;   // 16-bit (-32767..+32768) temperatures * 10
   end;
   PBrcStation = ^TBrcStation;
-  TBrcStations = array of TBrcStation;
+  TBrcStationDynArray = array of TBrcStation;
+
+  TBrcStations = array[word] of TBrcStation;
+  PBrcStations = ^TBrcStations;
 
   TBrcList = record
   public
-    Station: TBrcStations;
     Count: integer;
     {$ifdef CUSTOMHASH}
+    Station: PBrcStations; // perfectly aligned to 64 bytes from StationMem[]
     StationHash: array of word; // store 0 if void, or Station[] index + 1
+    StationMem: TBrcStationDynArray;
     function Search(name: pointer; namelen: PtrInt): PBrcStation;
     {$else}
+    Station: TBrcStationDynArray;
     Stations: TDynArrayHashed;
     function Search(name: PByteArray): PBrcStation;
     {$endif CUSTOMHASH}
-    procedure Init(max: integer);
+    procedure Init(max: integer; align: boolean);
   end;
 
   TBrcMain = class
   protected
     fSafe: TLightLock;
     fEvent: TSynEvent;
-    fRunning: integer;
+    fRunning, fMax: integer;
     fCurrentChunk: PByteArray;
     fCurrentRemain: PtrUInt;
     fList: TBrcList;
@@ -90,10 +95,14 @@   TBrcThread = class(TThread)
 const
   HASHSIZE = 1 shl 18; // slightly oversized to avoid most collisions
 
-procedure TBrcList.Init(max: integer);
+procedure TBrcList.Init(max: integer; align: boolean);
 begin
   assert(max <= high(StationHash[0]));
-  SetLength(Station, max);
+  SetLength(StationMem, max); // RTL won't align by 64 bytes
+  Station := pointer(StationMem);
+  if align then
+    while PtrUInt(Station) and 63 <> 0 do // manual alignment
+      inc(PByte(Station));
   SetLength(StationHash, HASHSIZE);
 end;
 
@@ -206,10 +215,11 @@ function StationComp(const A, B): integer;
   result := MemCmp(@sa.NameLen, @sb.NameLen, sa.NameLen + 1);
 end;
 
-procedure TBrcList.Init(max: integer);
+procedure TBrcList.Init(max: integer; align: boolean);
 begin
+  // align is just ignored, because TDynArray requires natural alignment
   Stations.Init(
-    TypeInfo(TBrcStations), Station, @StationHash, @StationComp, nil, @Count);
+    TypeInfo(TBrcStationDynArray), Station, @StationHash, @StationComp, nil, @Count);
   Stations.Capacity := max;
 end;
 
@@ -220,7 +230,7 @@ function TBrcList.Search(name: PByteArray): PBrcStation;
 begin
   assert(name^[0] < SizeOf(TBrcStation.NameText));
   i := Stations.FindHashedForAdding(name^, added);
-  result := @Station[i]; // in two steps (Station[] may be reallocated if added)
+  result := @Station[i]; // in two steps (Station[] may be reallocated)
   if not added then
     exit;
   MoveFast(name^, result^.NameLen, name^[0] + 1);
@@ -237,7 +247,7 @@ constructor TBrcThread.Create(owner: TBrcMain);
 begin
   fOwner := owner;
   FreeOnTerminate := true;
-  fList.Init(length(fOwner.fList.Station));
+  fList.Init(fOwner.fMax, {align=}true);
   InterlockedIncrement(fOwner.fRunning);
   inherited Create({suspended=}false);
 end;
@@ -328,7 +338,8 @@ constructor TBrcMain.Create(const fn: TFileName; threads, max: integer;
   fEvent := TSynEvent.Create;
   if not fMem.Map(fn) then
     raise ESynException.CreateUtf8('Impossible to find %', [fn]);
-  fList.Init(max);
+  fMax := max;
+  fList.Init(fMax, {align=}false); // not aligned for TDynArray.Sort to work
   fCurrentChunk := pointer(fMem.Buffer);
   fCurrentRemain := fMem.Size;
   core := 0;
@@ -391,30 +402,23 @@ procedure TBrcMain.Aggregate(const another: TBrcList);
   n: integer;
 begin
   fSafe.Lock; // several TBrcThread may finish at the same time
-  {$ifdef CUSTOMHASH}
-  if fList.Count = 0 then
-    fList := another // we can reuse the existing hash table
-  else
-  {$endif CUSTOMHASH}
-  begin
-    n := another.Count;
-    s := pointer(another.Station);
-    repeat
-      {$ifdef CUSTOMHASH}
-      d := fList.Search(@s^.NameText, s^.NameLen);
-      {$else}
-      d := fList.Search(@s^.NameLen);
-      {$endif CUSTOMHASH}
-      inc(d^.Count, s^.Count);
-      inc(d^.Sum, s^.Sum);
-      if s^.Max > d^.Max then
-        d^.Max := s^.Max;
-      if s^.Min < d^.Min then
-        d^.Min := s^.Min;
-      inc(s);
-      dec(n);
-    until n = 0;
-  end;
+  n := another.Count;
+  s := pointer(another.Station);
+  repeat
+    {$ifdef CUSTOMHASH}
+    d := fList.Search(@s^.NameText, s^.NameLen);
+    {$else}
+    d := fList.Search(@s^.NameLen);
+    {$endif CUSTOMHASH}
+    inc(d^.Count, s^.Count);
+    inc(d^.Sum, s^.Sum);
+    if s^.Max > d^.Max then
+      d^.Max := s^.Max;
+    if s^.Min < d^.Min then
+      d^.Min := s^.Min;
+    inc(s);
+    dec(n);
+  until n = 0;
   fSafe.UnLock;
   if InterlockedDecrement(fRunning) = 0 then
     fEvent.SetEvent; // all threads finished: release main console thread
@@ -482,8 +486,8 @@ function TBrcMain.SortedText: RawUtf8;
   tmp: TTextWriterStackBuffer;
 begin
   {$ifdef CUSTOMHASH}
-  DynArrayFakeLength(pointer(fList.Station), fList.Count);
-  DynArray(TypeInfo(TBrcStations), fList.Station).Sort(ByStationName);
+  DynArrayFakeLength(fList.Station, fList.Count);
+  DynArray(TypeInfo(TBrcStationDynArray), fList.Station).Sort(ByStationName);
   {$else}
   fList.Stations.Sort(ByStationName);
   {$endif CUSTOMHASH}
@@ -530,7 +534,8 @@ function TBrcMain.SortedText: RawUtf8;
   assert(SizeOf(TBrcStation) = 64); // 64 bytes = CPU L1 cache line size
   // read command line parameters
   Executable.Command.ExeDescription := 'The mORMot One Billion Row Challenge';
-  fn := Executable.Command.ArgString(0, 'the data source #filename');
+  if Executable.Command.Arg(0, 'the data source #filename') then
+    Utf8ToFileName(Executable.Command.Args[0], fn);
   verbose := Executable.Command.Option(
     ['v', 'verbose'], 'generate verbose output with timing');
   affinity := Executable.Command.Option(