commit 426b0f5a7a581bb9bddcf0dd1aa0a6316e4cb971
author TreeHugger Robot <treehugger-gerrit@google.com> Fri Dec 11 03:01:55 2020 +0000
committer Android (Google) Code Review <android-gerrit@google.com> Fri Dec 11 03:01:55 2020 +0000
tree f601d23e16f9ace6033183231bee762e1e039168
parent ab5299e6fe7a931b211e46ada3c7eb08db419b2a
parent ea5baf2b7a2a65de6c886ba3b207b55752b58637

Merge "BufferPool: limit number of idle buffers in caches" into mainline-prod

media/bufferpool/2.0/AccessorImpl.cpp

diff --git a/media/bufferpool/2.0/AccessorImpl.cpp b/media/bufferpool/2.0/AccessorImpl.cpp
index 6111fea..1d2562e 100644
--- a/media/bufferpool/2.0/AccessorImpl.cpp
+++ b/media/bufferpool/2.0/AccessorImpl.cpp
@@ -39,6 +39,8 @@
 
     static constexpr size_t kMinAllocBytesForEviction = 1024*1024*15;
     static constexpr size_t kMinBufferCountForEviction = 25;
+    static constexpr size_t kMaxUnusedBufferCount = 64;
+    static constexpr size_t kUnusedBufferCountTarget = kMaxUnusedBufferCount - 16;
 
     static constexpr nsecs_t kEvictGranularityNs = 1000000000; // 1 sec
     static constexpr nsecs_t kEvictDurationNs = 5000000000; // 5 secs
@@ -724,9 +726,11 @@
 }
 
 void Accessor::Impl::BufferPool::cleanUp(bool clearCache) {
-    if (clearCache || mTimestampUs > mLastCleanUpUs + kCleanUpDurationUs) {
+    if (clearCache || mTimestampUs > mLastCleanUpUs + kCleanUpDurationUs ||
+            mStats.buffersNotInUse() > kMaxUnusedBufferCount) {
         mLastCleanUpUs = mTimestampUs;
-        if (mTimestampUs > mLastLogUs + kLogDurationUs) {
+        if (mTimestampUs > mLastLogUs + kLogDurationUs ||
+                mStats.buffersNotInUse() > kMaxUnusedBufferCount) {
             mLastLogUs = mTimestampUs;
             ALOGD("bufferpool2 %p : %zu(%zu size) total buffers - "
                   "%zu(%zu size) used buffers - %zu/%zu (recycle/alloc) - "
@@ -737,8 +741,9 @@
                   mStats.mTotalFetches, mStats.mTotalTransfers);
         }
         for (auto freeIt = mFreeBuffers.begin(); freeIt != mFreeBuffers.end();) {
-            if (!clearCache && (mStats.mSizeCached < kMinAllocBytesForEviction
-                    || mBuffers.size() < kMinBufferCountForEviction)) {
+            if (!clearCache && mStats.buffersNotInUse() <= kUnusedBufferCountTarget &&
+                    (mStats.mSizeCached < kMinAllocBytesForEviction ||
+                     mBuffers.size() < kMinBufferCountForEviction)) {
                 break;
             }
             auto it = mBuffers.find(*freeIt);

media/bufferpool/2.0/AccessorImpl.h

diff --git a/media/bufferpool/2.0/AccessorImpl.h b/media/bufferpool/2.0/AccessorImpl.h
index cd1b4d0..3d39941 100644
--- a/media/bufferpool/2.0/AccessorImpl.h
+++ b/media/bufferpool/2.0/AccessorImpl.h
@@ -193,6 +193,12 @@
                 : mSizeCached(0), mBuffersCached(0), mSizeInUse(0), mBuffersInUse(0),
                   mTotalAllocations(0), mTotalRecycles(0), mTotalTransfers(0), mTotalFetches(0) {}
 
+            /// # of currently unused buffers
+            size_t buffersNotInUse() const {
+                ALOG_ASSERT(mBuffersCached >= mBuffersInUse);
+                return mBuffersCached - mBuffersInUse;
+            }
+
             /// A new buffer is allocated on an allocation request.
             void onBufferAllocated(size_t allocSize) {
                 mSizeCached += allocSize;

media/bufferpool/2.0/BufferPoolClient.cpp

diff --git a/media/bufferpool/2.0/BufferPoolClient.cpp b/media/bufferpool/2.0/BufferPoolClient.cpp
index 342fef6..9308b81 100644
--- a/media/bufferpool/2.0/BufferPoolClient.cpp
+++ b/media/bufferpool/2.0/BufferPoolClient.cpp
@@ -32,6 +32,8 @@
 static constexpr int64_t kReceiveTimeoutUs = 1000000; // 100ms
 static constexpr int kPostMaxRetry = 3;
 static constexpr int kCacheTtlUs = 1000000; // TODO: tune
+static constexpr size_t kMaxCachedBufferCount = 64;
+static constexpr size_t kCachedBufferCountTarget = kMaxCachedBufferCount - 16;
 
 class BufferPoolClient::Impl
         : public std::enable_shared_from_this<BufferPoolClient::Impl> {
@@ -136,6 +138,10 @@
             --mActive;
             mLastChangeUs = getTimestampNow();
         }
+
+        int cachedBufferCount() const {
+            return mBuffers.size() - mActive;
+        }
     } mCache;
 
     // FMQ - release notifier
@@ -668,10 +674,12 @@
 // should have mCache.mLock
 void BufferPoolClient::Impl::evictCaches(bool clearCache) {
     int64_t now = getTimestampNow();
-    if (now >= mLastEvictCacheUs + kCacheTtlUs || clearCache) {
+    if (now >= mLastEvictCacheUs + kCacheTtlUs ||
+            clearCache || mCache.cachedBufferCount() > kMaxCachedBufferCount) {
         size_t evicted = 0;
         for (auto it = mCache.mBuffers.begin(); it != mCache.mBuffers.end();) {
-            if (!it->second->hasCache() && (it->second->expire() || clearCache)) {
+            if (!it->second->hasCache() && (it->second->expire() ||
+                        clearCache || mCache.cachedBufferCount() > kCachedBufferCountTarget)) {
                 it = mCache.mBuffers.erase(it);
                 ++evicted;
             } else {