Version 3.1

Use a safer locking strategy for threads

Author: 68412542+EagleAglow@users.noreply.github.com

entries/bfire/README.md

@@ -60,9 +60,10 @@ tabulated data for each station.  Finally, the TStringList is sorted, and the da
 
 ## History
 
-- Version 1.0: first working version, based on TStringList.
-- Version 1.1: modified rounding to new baseline.
-- Version 2.0: use hashing, sort later.
-- Version 2.1: minor speed tweaks.
-- Version 2.2: try hash functions modification.
+- Version 1.0: First working version, based on TStringList.
+- Version 1.1: Modified rounding to new baseline.
+- Version 2.0: Use hashing, sort later.
+- Version 2.1: Minor speed tweaks.
+- Version 2.2: Try hash functions modification.
 - Version 3.0: Six threads: one to read, four to tabulate, one (console) to rule them all...
+- Version 3.1: Safer locking strategy

entries/bfire/src/MultiThreadUnit.pas

@@ -42,7 +42,7 @@   THashRecord = record // each array item is compiled data for a place
   DataBufferSize2: Integer = 1000001;
   DataBufferSize3: Integer = 1000001;
   DataBufferSize4: Integer = 1000001;
-  DataBufferCushion: Integer = 100000;
+  DataBufferCushion: Integer = 10000;
 
   // split points for stacks
   // ABCDE FGHIJK LMNOPQR STUVWXYZ (and extended)
@@ -91,12 +91,11 @@   THashRecord = record // each array item is compiled data for a place
   ParseDataQ_Done3: Boolean;
   ParseDataQ_Done4: Boolean;
 
-  StackMax1: Integer;  // sample stack count for peak value (approx.)
+  StackMax1: Integer; // sample stack count for peak value (approx.)
   StackMax2: Integer;
   StackMax3: Integer;
   StackMax4: Integer;
 
-
 procedure FileToArrays(inputFilename: String; UseStdOut: Boolean); // read
 procedure LaunchReadingThread(inputFilename: String);
 procedure LaunchTabulateThread1;
@@ -109,7 +108,6 @@ procedure ArrayToFile(outFile: String; UseStdOut: Boolean);
 
 implementation
 
-
 function IntegerFixup(something: Integer): String; inline;
 // fixup to adjust for storing tenths of degrees as integer
 // e.g. convert integer 234 to string 23.4 and -167 to -16.7
@@ -124,7 +122,6 @@ function IntegerFixup(something: Integer): String; inline;
   IntegerFixup := thing.Replace('-.', '-0.');
 end;
 
-
 function MeanFixup(total: Integer; count: Integer): String; inline;
 // fixup to adjust for storing tenths of degrees as integer
 // calculate mean to one decimal place, rounded up/down depending on sign
@@ -180,7 +177,6 @@ function MeanFixup(total: Integer; count: Integer): String; inline;
   MeanFixup := temp; // was temp;
 end;
 
-
 procedure SortArrays; inline;
 var
   i: Integer;
@@ -297,7 +293,6 @@ procedure ArrayToFile(outFile: String; UseStdOut: Boolean);
 
 end;
 
-
 procedure FileToArrays(inputFilename: String; UseStdOut: Boolean);
 var
   i: Integer;
@@ -362,7 +357,6 @@ procedure FileToArrays(inputFilename: String; UseStdOut: Boolean);
 
 end;
 
-
 procedure LaunchReadingThread(inputFilename: String);
 var
   ReadingThread: TThread;
@@ -409,93 +403,109 @@ procedure LaunchReadingThread(inputFilename: String);
                 if Choice <= SplitPoint1 then // A thru E
                 begin
                   while True do // break on success
+                  begin
+                    DataStackLock1.Acquire;
                     if (DataStackCount1 < DataBufferSize1 - 1) then
                     // there is room
                     begin
-                      DataStackLock1.Acquire;
                       DataStack1[DataStackCount1] := DataStackItem;
                       inc(DataStackCount1);
                       DataStackLock1.Release;
                       Break;
                     end
-                    else // need to waste a few cycles
+                    else // need to wait, hope for room later
                     begin
+                      DataStackLock1.Release;
                       while (DataStackCount1 > DataBufferSize1 -
                         DataBufferCushion) do
                       begin
                         // nothing real
-                        TimeOut := DataStackCount1 mod 16001;
+//                        TimeOut := DataStackCount1 mod 16001;
+//                        TimeOut := DataStackCount1 +1;
                       end;
                     end;
+                  end;
                 end
                 else // F thru K
                 begin
                   while True do // break on success
+                  begin
+                    DataStackLock2.Acquire;
                     if (DataStackCount2 < DataBufferSize2 - 1) then
                     // there is room
                     begin
-                      DataStackLock2.Acquire;
                       DataStack2[DataStackCount2] := DataStackItem;
                       inc(DataStackCount2);
                       DataStackLock2.Release;
                       Break;
                     end
-                    else // need to waste a few cycles
+                    else // need to wait, hope for room later
                     begin
+                      DataStackLock2.Release;
                       while (DataStackCount2 > DataBufferSize2 -
                         DataBufferCushion) do
                       begin
                         // nothing real
-                        TimeOut := DataStackCount2 mod 16001;
+//                        TimeOut := DataStackCount2 mod 16001;
+//                        TimeOut := DataStackCount2 +1;
                       end;
                     end;
+                  end;
                 end;
               end
               else // K and beyond
               begin
                 if Choice <= SplitPoint3 then // L thru R
                 begin
                   while True do // break on success
+                  begin
+                    DataStackLock3.Acquire;
                     if (DataStackCount3 < DataBufferSize3 - 1) then
                     // there is room
                     begin
-                      DataStackLock3.Acquire;
                       DataStack3[DataStackCount3] := DataStackItem;
                       inc(DataStackCount3);
                       DataStackLock3.Release;
                       Break;
                     end
-                    else // need to waste a few cycles
+                    else // need to wait, hope for room later
                     begin
+                      DataStackLock3.Release;
                       while (DataStackCount3 > DataBufferSize3 -
                         DataBufferCushion) do
                       begin
                         // nothing real
-                        TimeOut := DataStackCount3 mod 16001;
+//                        TimeOut := DataStackCount3 mod 16001;
+//                        TimeOut := DataStackCount3 +1;
                       end;
                     end;
+                  end;
                 end
                 else // S and beyond
                 begin
                   while True do // break on success
+                  begin
+                    DataStackLock4.Acquire;
                     if (DataStackCount4 < DataBufferSize4 - 1) then
                     // there is room
                     begin
-                      DataStackLock4.Acquire;
                       DataStack4[DataStackCount4] := DataStackItem;
                       inc(DataStackCount4);
                       DataStackLock4.Release;
                       Break;
                     end
-                    else // need to waste a few cycles
+                    else // need to wait, hope for room later
                     begin
+                      DataStackLock4.Release;
                       while (DataStackCount4 > DataBufferSize4 -
                         DataBufferCushion) do
                       begin
                         // nothing real
-                        TimeOut := DataStackCount4 mod 16001;
+//                        TimeOut := DataStackCount4 mod 16001;
+//                        TimeOut := DataStackCount4 +1;
                       end;
                     end;
+                  end;
                 end;
               end;
 
@@ -548,6 +558,7 @@ procedure LaunchTabulateThread1;
       G: Cardinal;
       Hash: Cardinal;
       BTT: Integer; // temporary for bytes to temperature conversion
+      TimeOut: Integer;
 
     begin
       while True do
@@ -556,9 +567,9 @@ procedure LaunchTabulateThread1;
         // get item from stack
         while True do // break on success
         begin
+          DataStackLock1.Acquire;
           if (DataStackCount1 > 0) then // there is data
           begin
-            DataStackLock1.Acquire;
             DataStackItem1 := DataStack1[DataStackCount1 - 1];
             dec(DataStackCount1);
             DataStackLock1.Release;
@@ -569,8 +580,12 @@ procedure LaunchTabulateThread1;
             if ReadFile_Done then // no more data
             begin
               ParseDataQ_Done1 := True;
+              DataStackLock1.Release;
               Break;
             end;
+            DataStackLock1.Release;
+            // nothing real
+            TimeOut := DataStackCount1 mod 16001;
           end;
         end;
 
@@ -747,6 +762,7 @@ procedure LaunchTabulateThread2;
       G: Cardinal;
       Hash: Cardinal;
       BTT: Integer; // temporary for bytes to temperature conversion
+      TimeOut: Integer;
 
     begin
       while True do
@@ -755,9 +771,9 @@ procedure LaunchTabulateThread2;
         // get item from stack
         while True do // break on success
         begin
+          DataStackLock2.Acquire;
           if (DataStackCount2 > 0) then // there is data
           begin
-            DataStackLock2.Acquire;
             DataStackItem2 := DataStack2[DataStackCount2 - 1];
             dec(DataStackCount2);
             DataStackLock2.Release;
@@ -768,8 +784,12 @@ procedure LaunchTabulateThread2;
             if ReadFile_Done then // no more data
             begin
               ParseDataQ_Done2 := True;
+              DataStackLock2.Release;
               Break;
             end;
+            DataStackLock2.Release;
+            // nothing real
+            TimeOut := DataStackCount2 mod 16001;
           end;
         end;
 
@@ -946,6 +966,7 @@ procedure LaunchTabulateThread3;
       G: Cardinal;
       Hash: Cardinal;
       BTT: Integer; // temporary for bytes to temperature conversion
+      TimeOut: Integer;
 
     begin
       while True do
@@ -954,9 +975,9 @@ procedure LaunchTabulateThread3;
         // get item from stack
         while True do // break on success
         begin
+          DataStackLock3.Acquire;
           if (DataStackCount3 > 0) then // there is data
           begin
-            DataStackLock3.Acquire;
             DataStackItem3 := DataStack3[DataStackCount3 - 1];
             dec(DataStackCount3);
             DataStackLock3.Release;
@@ -967,8 +988,12 @@ procedure LaunchTabulateThread3;
             if ReadFile_Done then // no more data
             begin
               ParseDataQ_Done3 := True;
+              DataStackLock3.Release;
               Break;
             end;
+            DataStackLock3.Release;
+            // nothing real
+            TimeOut := DataStackCount3 mod 16001;
           end;
         end;
 
@@ -1147,6 +1172,7 @@ procedure LaunchTabulateThread4;
       G: Cardinal;
       Hash: Cardinal;
       BTT: Integer; // temporary for bytes to temperature conversion
+      TimeOut: Integer;
 
     begin
       while True do
@@ -1155,9 +1181,9 @@ procedure LaunchTabulateThread4;
         // get item from stack
         while True do // break on success
         begin
+          DataStackLock4.Acquire;
           if (DataStackCount4 > 0) then // there is data
           begin
-            DataStackLock4.Acquire;
             DataStackItem4 := DataStack4[DataStackCount4 - 1];
             dec(DataStackCount4);
             DataStackLock4.Release;
@@ -1168,8 +1194,12 @@ procedure LaunchTabulateThread4;
             if ReadFile_Done then // no more data
             begin
               ParseDataQ_Done4 := True;
+              DataStackLock4.Release;
               Break;
             end;
+            DataStackLock4.Release;
+            // nothing real
+            TimeOut := DataStackCount4 mod 16001;
           end;
         end;
 

entries/bfire/src/version.inc

@@ -1,2 +1,2 @@
 const
-  cVersion = '3.0';
+  cVersion = '3.1';