Optimizations to papi-java

Christoph implemented some optimizations to avoid stopping counters when
it's not needed

I updated the client code to use the new API.

core/src/main/java/se/lth/cs/timing/CollectionTimer.java

@@ -66,7 +66,9 @@ public class CollectionTimer {
     }
 
     public long getCycles(OperationType operationType) {
-        return getEventSet(operationType).getCounters()[0];
+        long[] readings = new long[getEventSet(operationType).size()];
+        getEventSet(operationType).read(readings);
+        return readings[0];
     }
 
     public long getTotalTime() { return mainStopWatch.getNanoTime(); }
@@ -139,8 +141,7 @@ public class CollectionTimer {
         if (isTopLevel()) {
             suspendStopWatch(operationType);
             EventSet ev = getEventSet(operationType);
-            ev.stop();
-            cycles += ev.getCounters()[0];
+            cycles += ev.stop()[0];
         }
     }
 }

core/src/main/kotlin/se/lth/cs/papicounters/PapiRunner.kt

@@ -47,9 +47,8 @@ open class PapiRunner() : PapiBenchmarkAnalyzer {
                         b[i] = acc
                     }
                 }
-                evset.stop()
                 // Get data
-                val currentData = evset.counters
+                val currentData = evset.stop()
                 current.addAll(currentData.toList())
             }
             data.set(counter, current)
@@ -84,14 +83,14 @@ open class PapiRunner() : PapiBenchmarkAnalyzer {
             var accumulator = 0
             evset.start()
             app.runBenchmark(blackhole)
-            evset.stop()
+            val readings = evset.stop()
             val resultDataStructure = app.getDatastructure()
 
             // Write the result somewhere to prevent dead code elimination
             writer.write(accumulator)
             writer.write(resultDataStructure.toString())
             // We record the data
-            val runSamples = spec.counters().zip(evset.counters.toList()).map {
+            val runSamples = spec.counters().zip(readings.toList()).map {
                 PapiBenchmarkAnalyzer.BenchmarkRunSample(it.first, it.second.toDouble())
             }
             val runData = PapiBenchmarkAnalyzer.BenchmarkRunData(

core/src/main/kotlin/se/lth/cs/papicounters/PapiTracerRunner.kt

@@ -48,15 +48,19 @@ open class PapiTracerRunner() : PapiRunner() {
 
 
     fun makeRecords(text : String): List<TraceRecord> {
-        val cleanedLines = text.lines().filter { !it.isEmpty() }
+        val header = text.lines().first()
+        val columnIndex = header.trim().split("\t").mapIndexed { index, column -> Pair(column, index) }
+            .toMap()
+
+        val cleanedLines = text.lines().drop(1).filter { !it.isEmpty() }
 
         return cleanedLines.map { line ->
             val splitted = line.split("\t")
-            TraceRecord(splitted[0].intern(),
-                splitted[1].intern(),
-                Integer.parseInt(splitted[2]),
-                splitted[3].intern(),
-                splitted[4].intern()
+            TraceRecord(splitted[columnIndex["location"]!!].intern(),
+                splitted[columnIndex["feature"]!!].intern(),
+                Integer.parseInt(splitted[columnIndex["feature_value"]!!]),
+                splitted[columnIndex["collection"]!!].intern(),
+                splitted[columnIndex["method"]!!].intern()
             )
         }
     }
@@ -133,7 +137,7 @@ open class PapiTracerRunner() : PapiRunner() {
 
         // We get the output from the run
         val stream = ByteArrayOutputStream()
-        Tracer.printRecords(PrintStream(stream))
+        Tracer.printRecords(1, PrintStream(stream))
         return makeRecords(stream.toString())
     }
 

core/src/test/java/SyntheticBenchmarkTest.java

@@ -316,8 +316,7 @@ public class SyntheticBenchmarkTest {
                 }
                 // done with the code
 
-                evset.stop();
-                long[] data = evset.getCounters();
+                long[] data = evset.stop();
 
                 // only print the 10th run
                 if (warmup == 0) {

core/src/test/kotlin/TracingCollectionRunnerTest.kt

@@ -51,7 +51,7 @@ class TracingCollectionRunnerTest {
         b.runBenchmark(blackhole)
 
         val s = ByteArrayOutputStream()
-        Tracer.printRecords(PrintStream(s))
+        Tracer.printRecords(1, PrintStream(s))
         // We're gonna clean up the lines where we have 0 invocations
         val partitioned = s.toString().lines().partition {
             it.contains("invocations\t0")

papi-java @ 80d07230

-Subproject commit 16c467d838f2fedcfaa1b51659b98f4c031ab025
+Subproject commit 80d072309714821134720a126a46a8bd64ca88f0