Improve ProfileSaver to cache data and do minimal I/O
This CLs introducing caching to further optimize the I/O performed by
the ProfileSaver. The cache stats are also recorded.
Resolved classes are captured and cached after 2 seconds but written
later during application lifetime.
Methods are also cached and the write got smarter to avoid
reading/writing them if it's not needed.
On non scientific experiments the size of the cache reaches just a few
hundreds uint16_t values kept in set, so its impact is minimal.
In terms of how much data we write. In the same non scientific
experiments this reduces the total bytes written by at least 2-3x. In
the first few minutes of after the boot gmscore writes ~3KB (down from
9kb) and quicksearchlauncher writes ~20KB (down from 40KB).
Bug: 27600652
(cherry picked from commit 85f7bf3bbfa17d65ff77e3e826b5f7aff45838a9)
Change-Id: I6ecb04ce81b281d1c1538060dbbaeeeb08906775
diff --git a/runtime/jit/offline_profiling_info.cc b/runtime/jit/offline_profiling_info.cc
index e805ce1..e864d87 100644
--- a/runtime/jit/offline_profiling_info.cc
+++ b/runtime/jit/offline_profiling_info.cc
@@ -49,6 +49,79 @@
}
}
+bool ProfileCompilationInfo::AddMethodsAndClasses(
+ const std::vector<ArtMethod*>& methods,
+ const std::set<DexCacheResolvedClasses>& resolved_classes) {
+ ScopedObjectAccess soa(Thread::Current());
+ for (ArtMethod* method : methods) {
+ const DexFile* dex_file = method->GetDexFile();
+ if (!AddMethodIndex(GetProfileDexFileKey(dex_file->GetLocation()),
+ dex_file->GetLocationChecksum(),
+ method->GetDexMethodIndex())) {
+ return false;
+ }
+ }
+ for (const DexCacheResolvedClasses& dex_cache : resolved_classes) {
+ if (!AddResolvedClasses(dex_cache)) {
+ return false;
+ }
+ }
+ return true;
+}
+
+bool ProfileCompilationInfo::MergeAndSave(const std::string& filename, uint64_t* bytes_written) {
+ ScopedTrace trace(__PRETTY_FUNCTION__);
+ ScopedFlock flock;
+ std::string error;
+ if (!flock.Init(filename.c_str(), O_RDWR | O_NOFOLLOW | O_CLOEXEC, /* block */ false, &error)) {
+ LOG(WARNING) << "Couldn't lock the profile file " << filename << ": " << error;
+ return false;
+ }
+
+ int fd = flock.GetFile()->Fd();
+
+ // Load the file but keep a copy around to be able to infer if the content has changed.
+ ProfileCompilationInfo fileInfo;
+ if (!fileInfo.Load(fd)) {
+ LOG(WARNING) << "Could not load previous profile data from file " << filename;
+ return false;
+ }
+
+ // Merge the content of file into the current object.
+ if (!MergeWith(fileInfo)) {
+ LOG(WARNING) << "Could not merge previous profile data from file " << filename;
+ }
+
+ // If after the merge we have the same data as what is the file there's no point
+ // in actually doing the write. The file will be exactly the same as before.
+ if (Equals(fileInfo)) {
+ if (bytes_written != nullptr) {
+ *bytes_written = 0;
+ }
+ return true;
+ }
+
+ // We need to clear the data because we don't support append to the profiles yet.
+ if (!flock.GetFile()->ClearContent()) {
+ PLOG(WARNING) << "Could not clear profile file: " << filename;
+ return false;
+ }
+
+ // This doesn't need locking because we are trying to lock the file for exclusive
+ // access and fail immediately if we can't.
+ bool result = Save(fd);
+ if (result) {
+ VLOG(profiler) << "Successfully saved profile info to " << filename
+ << " Size: " << GetFileSizeBytes(filename);
+ if (bytes_written != nullptr) {
+ *bytes_written = GetFileSizeBytes(filename);
+ }
+ } else {
+ VLOG(profiler) << "Failed to save profile info to " << filename;
+ }
+ return result;
+}
+
bool ProfileCompilationInfo::SaveProfilingInfo(
const std::string& filename,
const std::vector<ArtMethod*>& methods,
@@ -62,54 +135,16 @@
return true;
}
- ScopedTrace trace(__PRETTY_FUNCTION__);
- ScopedFlock flock;
- std::string error;
- if (!flock.Init(filename.c_str(), O_RDWR | O_NOFOLLOW | O_CLOEXEC, /* block */ false, &error)) {
- LOG(WARNING) << "Couldn't lock the profile file " << filename << ": " << error;
- return false;
- }
-
- int fd = flock.GetFile()->Fd();
-
ProfileCompilationInfo info;
- if (!info.Load(fd)) {
- LOG(WARNING) << "Could not load previous profile data from file " << filename;
- return false;
- }
- {
- ScopedObjectAccess soa(Thread::Current());
- for (ArtMethod* method : methods) {
- const DexFile* dex_file = method->GetDexFile();
- if (!info.AddMethodIndex(GetProfileDexFileKey(dex_file->GetLocation()),
- dex_file->GetLocationChecksum(),
- method->GetDexMethodIndex())) {
- return false;
- }
- }
- for (const DexCacheResolvedClasses& dex_cache : resolved_classes) {
- info.AddResolvedClasses(dex_cache);
- }
- }
-
- if (!flock.GetFile()->ClearContent()) {
- PLOG(WARNING) << "Could not clear profile file: " << filename;
- return false;
- }
-
- // This doesn't need locking because we are trying to lock the file for exclusive
- // access and fail immediately if we can't.
- bool result = info.Save(fd);
- if (result) {
- VLOG(profiler) << "Successfully saved profile info to " << filename
- << " Size: " << GetFileSizeBytes(filename);
+ if (!info.AddMethodsAndClasses(methods, resolved_classes)) {
+ LOG(WARNING) << "Checksum mismatch when processing methods and resolved classes for "
+ << filename;
if (bytes_written != nullptr) {
- *bytes_written = GetFileSizeBytes(filename);
+ *bytes_written = 0;
}
- } else {
- VLOG(profiler) << "Failed to save profile info to " << filename;
+ return false;
}
- return result;
+ return info.MergeAndSave(filename, bytes_written);
}
static bool WriteToFile(int fd, const std::ostringstream& os) {
@@ -341,7 +376,7 @@
return true;
}
-bool ProfileCompilationInfo::Load(const ProfileCompilationInfo& other) {
+bool ProfileCompilationInfo::MergeWith(const ProfileCompilationInfo& other) {
for (const auto& other_it : other.info_) {
const std::string& other_dex_location = other_it.first;
const DexFileData& other_dex_data = other_it.second;
@@ -394,6 +429,14 @@
return total;
}
+uint32_t ProfileCompilationInfo::GetNumberOfResolvedClasses() const {
+ uint32_t total = 0;
+ for (const auto& it : info_) {
+ total += it.second.class_set.size();
+ }
+ return total;
+}
+
std::string ProfileCompilationInfo::DumpInfo(const std::vector<const DexFile*>* dex_files,
bool print_full_dex_location) const {
std::ostringstream os;
@@ -449,4 +492,10 @@
return ret;
}
+void ProfileCompilationInfo::ClearResolvedClasses() {
+ for (auto& pair : info_) {
+ pair.second.class_set.clear();
+ }
+}
+
} // namespace art