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Simplify PerformanceStats by removing generics
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We don't really need a generic tracepoint ID type, we can use a
String in all cases.
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@gharrma
gharrma committed Jul 10, 2020
1 parent b9b4e60 commit 409045d
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Showing 2 changed files with 49 additions and 57 deletions.
14 changes: 7 additions & 7 deletions src/main/java/com/android/tools/probes/LintDetectorStats.java
View file
Expand Up @@ -20,7 +20,7 @@

@SuppressWarnings("unused") // Used by reflection from YourKit.
public class LintDetectorStats {
private static final ClassStats classStats = new ClassStats();
private static final PerformanceStats perfStats = new PerformanceStats();

@MethodPattern({
"com.android.tools.lint.client.api.LintDriver:*(*)",
Expand All @@ -29,14 +29,14 @@ public class LintDetectorStats {
})
public static class WrapDetectors {

public static PerformanceStats.Tracepoint<Class<?>> onEnter(@ClassRef Class<?> clazz) {
return classStats.enter(clazz);
public static PerformanceStats.Tracepoint onEnter(@ClassRef Class<?> clazz) {
return perfStats.enter(clazz.getName());
}

public static void onExit(
@ClassRef Class<?> clazz,
@OnEnterResult PerformanceStats.Tracepoint<Class<?>> tracepoint) {
classStats.exit(clazz, tracepoint);
@OnEnterResult PerformanceStats.Tracepoint parentTracepoint) {
perfStats.exit(clazz.getName(), parentTracepoint);
}
}

Expand All @@ -47,9 +47,9 @@ public static void onExit(
public static class WrapAppEnv {

public static void onExit() {
classStats.dumpStats();
perfStats.dumpStats();
System.out.println("Clearing stats");
classStats.clear();
perfStats.clear();
}
}
}
92 changes: 42 additions & 50 deletions src/main/java/com/android/tools/probes/PerformanceStats.java
View file
Expand Up @@ -10,7 +10,7 @@
* Use by calling [enter] and [exit] before and after each traced method is called.
*/
@SuppressWarnings("SynchronizationOnLocalVariableOrMethodParameter")
public class PerformanceStats<K> {
class PerformanceStats {

// Tracking time and tracking allocations require very similar code, but
// an observation is that we never really want to track both simultaneously.
Expand All @@ -34,36 +34,36 @@ private static class MutableLong {
}

// Holds performance counters for a single tracepoint on a single thread.
static class Tracepoint<K> {
K key;
static class Tracepoint {
String id;
int depth;
long startMarker;
long resumeMarker;
long total;
long self;
long callCount;

Tracepoint(K k) { key = k; }
Tracepoint(String id) { this.id = id; }
}

private static class ThreadState<K> {
Map<K, Tracepoint<K>> tracepoints = new HashMap<>();
Tracepoint<K> currTracepoint;
private static class ThreadState {
Map<String, Tracepoint> tracepoints = new HashMap<>();
Tracepoint currTracepoint;
}

// Holds the state from all threads. Protected by monitor.
private final List<ThreadState<K>> allState = new ArrayList<>();
private final List<ThreadState> allState = new ArrayList<>();

// Holds the state for the current thread. Protected by monitor because it is accessed by the stat dumping thread.
ThreadLocal<ThreadState<K>> localState = ThreadLocal.withInitial(() -> {
ThreadState<K> state = new ThreadState<>();
ThreadLocal<ThreadState> localState = ThreadLocal.withInitial(() -> {
ThreadState state = new ThreadState();
synchronized (allState) { allState.add(state); }
return state;
});

void clear() {
synchronized (allState) {
for (ThreadState<K> state : allState) {
for (ThreadState state : allState) {
synchronized (state) {
state.tracepoints.clear();
state.currTracepoint = null;
Expand All @@ -72,25 +72,25 @@ void clear() {
}
}

private Tracepoint<K> getTracepoint(ThreadState<K> state, K key) {
private Tracepoint getTracepoint(ThreadState state, String id) {
// As an optimization we try to reuse the last tracepoint. This is
// especially useful for recursive functions, for example.
Tracepoint<K> cached = state.currTracepoint;
if (cached != null && key.equals(cached.key))
Tracepoint cached = state.currTracepoint;
if (cached != null && id.equals(cached.id))
return cached;
return state.tracepoints.computeIfAbsent(key, Tracepoint::new);
return state.tracepoints.computeIfAbsent(id, Tracepoint::new);
}

// Note: returns the parent tracepoint to be stored on the stack.
Tracepoint<K> enter(K key) {
ThreadState<K> threadState = localState.get();
Tracepoint enter(String id) {
ThreadState threadState = localState.get();
synchronized (threadState) { // Almost no contention.
Tracepoint<K> parent = threadState.currTracepoint;
Tracepoint<K> tracepoint = getTracepoint(threadState, key);
Tracepoint parent = threadState.currTracepoint;
Tracepoint tracepoint = getTracepoint(threadState, id);

tracepoint.callCount++;

if (parent == null || !key.equals(parent.key)) {
if (parent == null || !id.equals(parent.id)) {
threadState.currTracepoint = tracepoint;

long now = measure();
Expand All @@ -110,12 +110,12 @@ Tracepoint<K> enter(K key) {
}

// Note: takes the parent tracepoint returned from [enter].
void exit(K key, Tracepoint<K> parent) {
ThreadState<K> threadState = localState.get();
void exit(String id, Tracepoint parent) {
ThreadState threadState = localState.get();
synchronized (threadState) {
Tracepoint<K> tracepoint = getTracepoint(threadState, key);
Tracepoint tracepoint = getTracepoint(threadState, id);

if (parent == null || !key.equals(parent.key)) {
if (parent == null || !id.equals(parent.id)) {
threadState.currTracepoint = parent;

long now = measure();
Expand All @@ -136,23 +136,23 @@ private long measure() {
return trackingAllocations ? totalAllocations.get().value : System.nanoTime();
}

public void dumpStats(PrintWriter w) {
void dumpStats(PrintWriter w) {
w.println();

Map<K, Tracepoint<K>> tallies = new HashMap<>();
List<ThreadState<K>> state;
Map<String, Tracepoint> tallies = new HashMap<>();
List<ThreadState> state;
synchronized (allState) { state = new ArrayList<>(allState); }
for (ThreadState<K> threadState : state) {
for (ThreadState threadState : state) {
synchronized (threadState) {
for (Map.Entry<K, Tracepoint<K>> e : threadState.tracepoints.entrySet()) {
K key = e.getKey();
Tracepoint<K> tracepoint = e.getValue();
Tracepoint<K> tally = tallies.computeIfAbsent(key, Tracepoint::new);
for (Map.Entry<String, Tracepoint> e : threadState.tracepoints.entrySet()) {
String id = e.getKey();
Tracepoint tracepoint = e.getValue();
Tracepoint tally = tallies.computeIfAbsent(id, Tracepoint::new);
tally.total += tracepoint.total;
tally.self += tracepoint.self;
tally.callCount += tracepoint.callCount;
if (tracepoint.depth > 0) {
w.println("WARNING: " + prettyPrintKey(key) + " is still on the stack");
w.println("WARNING: " + prettyPrintId(id) + " is still on the stack");
}
}
}
Expand All @@ -161,48 +161,40 @@ public void dumpStats(PrintWriter w) {
w.println("Lint detector performance stats:");

int spacing = tallies.keySet().stream()
.map(it -> prettyPrintKey(it).length())
.map(it -> prettyPrintId(it).length())
.max(Comparator.naturalOrder())
.orElse(0);
spacing += 2;
String format = "%" + spacing + "s %13s %13s %13s";
w.println(String.format(format, "", "total", "self", "calls"));

tallies.values().stream()
.sorted(Comparator.comparingLong((Tracepoint<K> tracepoint) -> tracepoint.total).reversed())
.sorted(Comparator.comparingLong((Tracepoint tracepoint) -> tracepoint.total).reversed())
.forEach(it ->
w.println(String.format(
format,
prettyPrintKey(it.key),
prettyPrintId(it.id),
prettyPrintValue(it.total),
prettyPrintValue(it.self),
it.callCount
))
);
}

public void dumpStats() {
void dumpStats() {
PrintWriter writer = new PrintWriter(System.out);
dumpStats(writer);
writer.flush();
}

protected String prettyPrintKey(K key) {
return key.toString();
private String prettyPrintId(String id) {
// Assumes the IDs are class names.
int lastDot = id.lastIndexOf('.');
return lastDot == -1 ? id : id.substring(lastDot + 1);
}

protected String prettyPrintValue(long value) {
private String prettyPrintValue(long value) {
String unit = trackingAllocations ? "MB" : "ms";
return (value / 1_000_000) + " " + unit;
}
}

// Convenience subclass for when the keys are class objects.
class ClassStats extends PerformanceStats<Class<?>> {
@Override
public String prettyPrintKey(Class<?> key) {
String name = key.getName();
int lastDot = name.lastIndexOf('.');
return lastDot == -1 ? name : name.substring(lastDot + 1);
}
}

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