Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(138)

Unified Diff: include/v8-profiler.h

Issue 1618693004: Revert "Revert of [profiler] Implement POC Sampling Heap Profiler (patchset #12 id:220001 of https:… (Closed) Base URL: https://chromium.googlesource.com/v8/v8.git@master
Patch Set: Add flag to suppress randomness from sampling heap profiler tests Created 4 years, 11 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
« no previous file with comments | « BUILD.gn ('k') | src/api.cc » ('j') | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
Index: include/v8-profiler.h
diff --git a/include/v8-profiler.h b/include/v8-profiler.h
index e432600290c6bb3e6749e7836b916eb5e0315e17..a991aa059d18b4d70e35e1e3da8b46183598c86b 100644
--- a/include/v8-profiler.h
+++ b/include/v8-profiler.h
@@ -419,6 +419,90 @@ class V8_EXPORT ActivityControl { // NOLINT
/**
+ * AllocationProfile is a sampled profile of allocations done by the program.
+ * This is structured as a call-graph.
+ */
+class V8_EXPORT AllocationProfile {
+ public:
+ struct Allocation {
+ /**
+ * Size of the sampled allocation object.
+ */
+ size_t size;
+
+ /**
+ * The number of objects of such size that were sampled.
+ */
+ unsigned int count;
+ };
+
+ /**
+ * Represents a node in the call-graph.
+ */
+ struct Node {
+ /**
+ * Name of the function. May be empty for anonymous functions or if the
+ * script corresponding to this function has been unloaded.
+ */
+ Local<String> name;
+
+ /**
+ * Name of the script containing the function. May be empty if the script
+ * name is not available, or if the script has been unloaded.
+ */
+ Local<String> script_name;
+
+ /**
+ * id of the script where the function is located. May be equal to
+ * v8::UnboundScript::kNoScriptId in cases where the script doesn't exist.
+ */
+ int script_id;
+
+ /**
+ * Start position of the function in the script.
+ */
+ int start_position;
+
+ /**
+ * 1-indexed line number where the function starts. May be
+ * kNoLineNumberInfo if no line number information is available.
+ */
+ int line_number;
+
+ /**
+ * 1-indexed column number where the function starts. May be
+ * kNoColumnNumberInfo if no line number information is available.
+ */
+ int column_number;
+
+ /**
+ * List of callees called from this node for which we have sampled
+ * allocations. The lifetime of the children is scoped to the containing
+ * AllocationProfile.
+ */
+ std::vector<Node*> children;
+
+ /**
+ * List of self allocations done by this node in the call-graph.
+ */
+ std::vector<Allocation> allocations;
+ };
+
+ /**
+ * Returns the root node of the call-graph. The root node corresponds to an
+ * empty JS call-stack. The lifetime of the returned Node* is scoped to the
+ * containing AllocationProfile.
+ */
+ virtual Node* GetRootNode() = 0;
+
+ virtual ~AllocationProfile() {}
+
+ static const int kNoLineNumberInfo = Message::kNoLineNumberInfo;
+ static const int kNoColumnNumberInfo = Message::kNoColumnInfo;
+};
+
+
+/**
* Interface for controlling heap profiling. Instance of the
* profiler can be retrieved using v8::Isolate::GetHeapProfiler.
*/
@@ -522,6 +606,49 @@ class V8_EXPORT HeapProfiler {
void StopTrackingHeapObjects();
/**
+ * Starts gathering a sampling heap profile. A sampling heap profile is
+ * similar to tcmalloc's heap profiler and Go's mprof. It samples object
+ * allocations and builds an online 'sampling' heap profile. At any point in
+ * time, this profile is expected to be a representative sample of objects
+ * currently live in the system. Each sampled allocation includes the stack
+ * trace at the time of allocation, which makes this really useful for memory
+ * leak detection.
+ *
+ * This mechanism is intended to be cheap enough that it can be used in
+ * production with minimal performance overhead.
+ *
+ * Allocations are sampled using a randomized Poisson process. On average, one
+ * allocation will be sampled every |sample_interval| bytes allocated. The
+ * |stack_depth| parameter controls the maximum number of stack frames to be
+ * captured on each allocation.
+ *
+ * NOTE: This is a proof-of-concept at this point. Right now we only sample
+ * newspace allocations. Support for paged space allocation (e.g. pre-tenured
+ * objects, large objects, code objects, etc.) and native allocations
+ * doesn't exist yet, but is anticipated in the future.
+ *
+ * Objects allocated before the sampling is started will not be included in
+ * the profile.
+ *
+ * Returns false if a sampling heap profiler is already running.
+ */
+ bool StartSamplingHeapProfiler(uint64_t sample_interval = 512 * 1024,
+ int stack_depth = 16);
+
+ /**
+ * Stops the sampling heap profile and discards the current profile.
+ */
+ void StopSamplingHeapProfiler();
+
+ /**
+ * Returns the sampled profile of allocations allocated (and still live) since
+ * StartSamplingHeapProfiler was called. The ownership of the pointer is
+ * transfered to the caller. Returns nullptr if sampling heap profiler is not
+ * active.
+ */
+ AllocationProfile* GetAllocationProfile();
+
+ /**
* Deletes all snapshots taken. All previously returned pointers to
* snapshots and their contents become invalid after this call.
*/
« no previous file with comments | « BUILD.gn ('k') | src/api.cc » ('j') | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698