When running with <= 4 system threads, only run one renderthread slice at a time
If the user doesn't have hyperthreading or has an older machine with
fewer cores, it can be advantageous to run only one renderthread slice
at a time.
Note: Vulkan must run in unlimited because order maintenance operations
require coordination between more than one thread (see
vkCommandBufferHostSyncGOOGLE)
Manual cherry-pick from aosp/1478711
Change-Id: I45ad0910fee4826037fb740a8b1f9087a7faf4c6
diff --git a/stream-servers/RenderThread.cpp b/stream-servers/RenderThread.cpp
index 39201fa..5d223ca 100644
--- a/stream-servers/RenderThread.cpp
+++ b/stream-servers/RenderThread.cpp
@@ -33,12 +33,17 @@
#include "base/System.h"
#include "base/Tracing.h"
#include "base/StreamSerializing.h"
+#include "base/Lock.h"
#include "base/MessageChannel.h"
#define EMUGL_DEBUG_LEVEL 0
#include "host-common/crash_reporter.h"
#include "host-common/debug.h"
+#ifndef _WIN32
+#include <unistd.h>
+#endif
+
#include <assert.h>
#include <string.h>
@@ -61,6 +66,17 @@
return false;
}
+static int getCpuCoreCount() {
+#ifdef _WIN32
+ SYSTEM_INFO si = {};
+ ::GetSystemInfo(&si);
+ return si.dwNumberOfProcessors < 1 ? 1 : si.dwNumberOfProcessors;
+#else
+ auto res = (int)sysconf(_SC_NPROCESSORS_ONLN);
+ return res < 1 ? 1 : res;
+#endif
+}
+
static uint64_t currTimeUs(bool enable) {
if (enable) {
return android::base::getHighResTimeUs();
@@ -72,10 +88,18 @@
// Start with a smaller buffer to not waste memory on a low-used render threads.
static constexpr int kStreamBufferSize = 128 * 1024;
+// Requires this many threads on the system available to run unlimited.
+static constexpr int kMinThreadsToRunUnlimited = 5;
+
+// A thread run limiter that limits render threads to run one slice at a time.
+static android::base::Lock sThreadRunLimiter;
+
RenderThread::RenderThread(RenderChannelImpl* channel,
android::base::Stream* loadStream)
: android::base::Thread(android::base::ThreadFlags::MaskSignals, 2 * 1024 * 1024),
- mChannel(channel) {
+ mChannel(channel),
+ mRunInLimitedMode(getCpuCoreCount() < kMinThreadsToRunUnlimited)
+{
if (loadStream) {
const bool success = loadStream->getByte();
if (success) {
@@ -395,6 +419,10 @@
do {
+ if (mRunInLimitedMode) {
+ sThreadRunLimiter.lock();
+ }
+
progress = false;
size_t last;
@@ -411,6 +439,10 @@
}
}
+ if (mRunInLimitedMode) {
+ sThreadRunLimiter.unlock();
+ }
+
// try to process some of the command buffer using the GLESv1
// decoder
//
