platform_system_core/logd/LogReader.h
Hao Wang f6e2296953 logd: enhance multiple blocking readers performance
logd suffers performance degradation when multiple blocking
readers connect to it. Each time when the writer thread log
new entries, all of the readers are notified regardless of
which log id they are watching.

In this case, only give notification to the readers who are
actually watching new entries' log id. This decreases logd
CPU consumption by skipping unnecessary LogBuffer::flushTo
loops.

Test: liblog-unit-tests, logd-unit-tests & CtsLiblogTestCases
      logcat-unit-tests
Test: manual:
1.'logcat –b all' at constant heavy logging load level
2.simultaneously 'logcat –b crash' in another session,
   a healthy crash buffer usually keep empty
3.logd CPU consumption doesn't increase after step 2

Change-Id: I4ffc045c9feb7a0998f7e47ae2173f8f6aa28e8a
2017-12-05 18:46:24 +08:00

48 lines
1.2 KiB
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Executable file

/*
* Copyright (C) 2012-2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef _LOGD_LOG_WRITER_H__
#define _LOGD_LOG_WRITER_H__
#include <sysutils/SocketListener.h>
#include "LogTimes.h"
#define LOGD_SNDTIMEO 32
class LogBuffer;
class LogReader : public SocketListener {
LogBuffer& mLogbuf;
public:
explicit LogReader(LogBuffer* logbuf);
void notifyNewLog(log_mask_t logMask);
LogBuffer& logbuf(void) const {
return mLogbuf;
}
protected:
virtual bool onDataAvailable(SocketClient* cli);
private:
static int getLogSocket();
void doSocketDelete(SocketClient* cli);
};
#endif