commit 47178c2d75ab261903ab859c28ecd10ffe90d212
author Andy Hung <hunga@google.com> Thu Jun 18 18:57:35 2020 -0700
committer Andy Hung <hunga@google.com> Fri Jun 19 12:27:47 2020 -0700
tree ff9b1743ced2b7d812dcf404224fa27fa7561129
parent 453044a3a0b190548ef15b27201444617bfec5d9

MediaMetrics: Tune garbage collection

Reduce thresholds for garbage collection.
Track the number of gcs in the dumpsys.

Test: 30x repeated invocation of AudioTrackTest
Test: adb shell showmap '$(pgrep -f audioserver)'
Test: adb shell dumpsys media.metrics --all
Bug: 159410113
Change-Id: I3ff7bb84bc45e44fe3d5ea84fecdf05c76cf5733

services/mediametrics/TransactionLog.h

diff --git a/services/mediametrics/TransactionLog.h b/services/mediametrics/TransactionLog.h
index 8a22826..0ca4639 100644
--- a/services/mediametrics/TransactionLog.h
+++ b/services/mediametrics/TransactionLog.h
@@ -43,9 +43,9 @@
     // Transaction Log between the Low Water Mark and the High Water Mark.
 
     // low water mark
-    static inline constexpr size_t kLogItemsLowWater = 5000;
+    static inline constexpr size_t kLogItemsLowWater = 1700;
     // high water mark
-    static inline constexpr size_t kLogItemsHighWater = 10000;
+    static inline constexpr size_t kLogItemsHighWater = 2000;
 
     // Estimated max data usage is 1KB * kLogItemsHighWater.
 
@@ -79,6 +79,7 @@
         std::lock_guard lock2(other.mLock);
         mLog = other.mLog;
         mItemMap = other.mItemMap;
+        mGarbageCollectionCount = other.mGarbageCollectionCount.load();
 
         return *this;
     }
@@ -181,6 +182,11 @@
         std::lock_guard lock(mLock);
         mLog.clear();
         mItemMap.clear();
+        mGarbageCollectionCount = 0;
+    }
+
+    size_t getGarbageCollectionCount() const {
+        return mGarbageCollectionCount;
     }
 
 private:
@@ -216,8 +222,6 @@
     bool gc(std::vector<std::any>& garbage) REQUIRES(mLock) {
         if (mLog.size() < mHighWaterMark) return false;
 
-        ALOGD("%s: garbage collection", __func__);
-
         auto eraseEnd = mLog.begin();
         size_t toRemove = mLog.size() - mLowWaterMark;
         // remove at least those elements.
@@ -265,6 +269,7 @@
         ALOGD("%s(%zu, %zu): log size:%zu item map size:%zu, item map items:%zu",
                 __func__, mLowWaterMark, mHighWaterMark,
                 mLog.size(), mItemMap.size(), itemMapCount);
+        ++mGarbageCollectionCount;
         return true;
     }
 
@@ -287,6 +292,8 @@
     const size_t mLowWaterMark = kLogItemsLowWater;
     const size_t mHighWaterMark = kLogItemsHighWater;
 
+    std::atomic<size_t> mGarbageCollectionCount{};
+
     mutable std::mutex mLock;
 
     MapTimeItem mLog GUARDED_BY(mLock);