Stores long-term histogram, outlier information
Moves analysis and storage from NBLog to
PerformanceAnalysis. Applies peak analysis to
outlier information to detect changes in the
distribution of outlier frequency.
Adds cleanup, documentation, FIXME comments for
upcoming changes.
Test: dumpsys media.log
Change-Id: Iea393dac62959aef754ae2a9b4afe2556c1f3ecb
diff --git a/media/libnbaio/NBLog.cpp b/media/libnbaio/NBLog.cpp
index e3f4876..2b5b4ff 100644
--- a/media/libnbaio/NBLog.cpp
+++ b/media/libnbaio/NBLog.cpp
@@ -892,23 +892,14 @@
ofs.close();
}
-// converts a time series into a map. key: buffer period length. value: count
-static std::map<int, int> buildBuckets(const std::vector<int64_t> &samples) {
- // TODO allow buckets of variable resolution
- std::map<int, int> buckets;
- for (size_t i = 1; i < samples.size(); ++i) {
- ++buckets[deltaMs(samples[i - 1], samples[i])];
- }
- return buckets;
-}
-
void NBLog::Reader::dump(int fd, size_t indent, NBLog::Reader::Snapshot &snapshot)
{
// CallStack cs(LOG_TAG);
mFd = fd;
mIndent = indent;
String8 timestamp, body;
- PerformanceAnalysis performanceAnalyzer; // used to call analysis functions
+ // FIXME: this is not thread safe
+ static PerformanceAnalysis performanceAnalysis; // used to store data and to call analysis functions
size_t lost = snapshot.lost() + (snapshot.begin() - EntryIterator(snapshot.data()));
if (lost > 0) {
body.appendFormat("warning: lost %zu bytes worth of events", lost);
@@ -930,29 +921,7 @@
memcpy(&hash, &(data->hash), sizeof(hash));
int64_t ts;
memcpy(&ts, &data->ts, sizeof(ts));
- const std::pair<log_hash_t, int> key(hash, data->author);
- // TODO might want to filter excessively high outliers, which are usually caused
- // by the thread being inactive.
- mHists[key].push_back(ts);
- // store time series data for each reader in order to bucket it once there
- // is enough data. Then, it is written to recentHists as a histogram.
- mTimeStampSeries[data->author].push_back(ts);
- // if length of the time series has reached kShortHistSize samples, do 1) and 2):
- if (mTimeStampSeries[data->author].size() >= kShortHistSize) {
- // 1) analyze the series to store all outliers and their exact timestamps:
- performanceAnalyzer.storeOutlierData(data->author, mTimeStampSeries[data->author]);
- // 2) compute its histogram, append this to mRecentHists and erase the time series
- mRecentHists.emplace_front(data->author,
- buildBuckets(mTimeStampSeries[data->author]));
- // do not let mRecentHists exceed capacity
- // TODO: turn the FIFO queue into a circular buffer
- if (mRecentHists.size() >= kRecentHistsCapacity) {
- mRecentHists.pop_back();
- }
- mTimeStampSeries.erase(data->author);
- }
- // if an element in mHists has not grown for a long time, delete
- // TODO copy histogram data only to mRecentHistsBuffer and pop oldest
+ performanceAnalysis.logTsEntry(data->author, ts);
++entry;
break;
}
@@ -967,12 +936,10 @@
break;
}
}
- performanceAnalyzer.reportPerformance(&body, mRecentHists);
+ performanceAnalysis.reportPerformance(&body);
if (!body.isEmpty()) {
dumpLine(timestamp, body);
}
- // comment in for tests
- // performanceAnalyzer.testFunction();
}
void NBLog::Reader::dump(int fd, size_t indent)