CheckpointThread Class Reference

CheckpointThread is dedicated to listening for checkpoint requests and carrying them out. More...

#include <CheckpointThread.h>

Inheritance diagram for CheckpointThread:

Thread SynchMonitoredObject ClosableObject CheckpointProvider List of all members.

Public Member Functions

 CheckpointThread (Database &database)
 Creates a checkpoint thread for the given database (no more than one is ever needed).
SXMutex & getActionMutex ()
 Gets the action mutex.
virtual void requestCheckpoint (CheckpointType checkpointType)
 Implements CheckpointProvider by signalling the checkpoint thread, which in response will quiesce the system and carry out a checkpoint.
virtual void start ()
 Spawns the OS thread.
void join ()
 Waits for the OS thread to terminate.
bool isStarted () const
 
Returns:
true if start has been called (and subsequent join has not completed)

bool isStopped () const
 
Returns:
opposite of isStarted()

boost::thread & getBoostThread ()
 Accesses the underlying boost::thread, e.g.
std::string getName ()
void setName (std::string const &s)
bool isClosed () const
 
Returns:
whether the object has been closed

void close ()
 Closes this object, releasing any unallocated resources.

Protected Member Functions

void initAndRun ()
virtual void beforeRun ()
virtual void afterRun ()

Protected Attributes

boost::thread * pBoostThread
bool bRunning
std::string name
StrictMutex mutex
LocalCondition condition
bool needsClose

Private Member Functions

void closeImpl ()
 Implements ClosableObject by requesting that the checkpoint thread shut itself down.
virtual void run ()

Private Attributes

Database & database
SXMutex actionMutex
CheckpointType checkpointType
bool quit

Detailed Description

CheckpointThread is dedicated to listening for checkpoint requests and carrying them out.

Definition at line 38 of file CheckpointThread.h.

Constructor & Destructor Documentation

CheckpointThread::CheckpointThread ( Database &  database  )  [explicit]

Creates a checkpoint thread for the given database (no more than one is ever needed).

This constructor does not start the thread; that must be done explicitly.

Parameters:
database the Database to checkpoint when requested

Definition at line 30 of file CheckpointThread.cpp.

References actionMutex, CHECKPOINT_DISCARD, checkpointType, quit, SXMutex::SCHEDULE_FAVOR_EXCLUSIVE, and SXMutex::setSchedulingPolicy().

00031     : database(databaseInit)
00032 {
00033     actionMutex.setSchedulingPolicy(SXMutex::SCHEDULE_FAVOR_EXCLUSIVE);
00034     checkpointType = CHECKPOINT_DISCARD;
00035     quit = false;
00036 }

Member Function Documentation

void CheckpointThread::closeImpl (  )  [private, virtual]

Implements ClosableObject by requesting that the checkpoint thread shut itself down.

Implements ClosableObject.

Definition at line 68 of file CheckpointThread.cpp.

References SynchMonitoredObject::condition, Thread::isStarted(), Thread::join(), SynchMonitoredObject::mutex, and quit.

00069 {
00070     StrictMutexGuard mutexGuard(mutex);
00071 
00072     if (!isStarted()) {
00073         return;
00074     }
00075 
00076     quit = true;
00077     condition.notify_all();
00078     mutexGuard.unlock();
00079 
00080     join();
00081 }

void CheckpointThread::run (  )  [private, virtual]

Implements Thread.

Definition at line 38 of file CheckpointThread.cpp.

References actionMutex, CHECKPOINT_DISCARD, Database::checkpointImpl(), checkpointType, SynchMonitoredObject::condition, database, SynchMonitoredObject::mutex, quit, and SXMutexGuard< lockMode >::unlock().

00039 {
00040     for (;;) {
00041         StrictMutexGuard mutexGuard(mutex);
00042         while ((checkpointType == CHECKPOINT_DISCARD) && !quit) {
00043             condition.wait(mutexGuard);
00044         }
00045         if (quit) {
00046             return;
00047         }
00048 
00049         // NOTE jvs 28-Feb-2006:  reset checkpointType here; we used
00050         // to do it after checkpoint completion, but that led to a
00051         // race condition whereby we might miss a new checkpoint request
00052         // by overwriting it.
00053         CheckpointType currentType = checkpointType;
00054         checkpointType = CHECKPOINT_DISCARD;
00055         mutexGuard.unlock();
00056 
00057         SXMutexExclusiveGuard actionMutexGuard(actionMutex);
00058         database.checkpointImpl(currentType);
00059         actionMutexGuard.unlock();
00060     }
00061 }

SXMutex & CheckpointThread::getActionMutex (  ) 

Gets the action mutex.

The checkpoint thread takes an exclusive lock on this mutex for the duration of each checkpoint, so any thread which needs to carry out an action which must not overlap a checkpoint should take a shared lock on this for the duration of the action.

Returns:
the mutex

Definition at line 63 of file CheckpointThread.cpp.

References actionMutex.

00064 {
00065     return actionMutex;
00066 }

void CheckpointThread::requestCheckpoint ( CheckpointType  checkpointType  )  [virtual]

Implements CheckpointProvider by signalling the checkpoint thread, which in response will quiesce the system and carry out a checkpoint.

Parameters:
checkpointType type of checkpoint to request

Implements CheckpointProvider.

Definition at line 83 of file CheckpointThread.cpp.

References CHECKPOINT_DISCARD, CHECKPOINT_FLUSH_ALL, CHECKPOINT_FLUSH_FUZZY, checkpointType, SynchMonitoredObject::condition, and SynchMonitoredObject::mutex.

00084 {
00085     StrictMutexGuard mutexGuard(mutex);
00086     switch (request) {
00087     case CHECKPOINT_FLUSH_ALL:
00088         checkpointType = request;
00089         break;
00090     case CHECKPOINT_FLUSH_FUZZY:
00091         if (checkpointType == CHECKPOINT_DISCARD) {
00092             checkpointType = request;
00093         }
00094         break;
00095     default:
00096         permAssert(false);
00097     }
00098     condition.notify_all();
00099 }

void Thread::initAndRun (  )  [protected, inherited]

Definition at line 66 of file Thread.cpp.

References Thread::afterRun(), Thread::beforeRun(), and Thread::run().

Referenced by Thread::start().

00067 {
00068     beforeRun();
00069     run();
00070     afterRun();
00071 }

void Thread::beforeRun (  )  [protected, virtual, inherited]

Definition at line 73 of file Thread.cpp.

References Thread::bRunning.

Referenced by Thread::initAndRun().

00074 {
00075     bRunning = true;
00076 }

void Thread::afterRun (  )  [protected, virtual, inherited]

Definition at line 78 of file Thread.cpp.

References Thread::bRunning.

Referenced by Thread::initAndRun().

00079 {
00080     bRunning = false;
00081 }

void Thread::start (  )  [virtual, inherited]

Spawns the OS thread.

Definition at line 50 of file Thread.cpp.

References Thread::initAndRun(), and Thread::pBoostThread.

Referenced by AioLinuxScheduler::AioLinuxScheduler(), AioPollingScheduler::AioPollingScheduler(), StatsTimer::start(), ResourceTest::testConcurrency(), and LocalConditionTest::testNotifyAll().

00051 {
00052     pBoostThread = new boost::thread(
00053         boost::bind(&Thread::initAndRun,this));
00054 }

void Thread::join (  )  [inherited]

Waits for the OS thread to terminate.

Definition at line 56 of file Thread.cpp.

References Thread::pBoostThread.

Referenced by closeImpl(), TimerThread::stop(), AioPollingScheduler::stop(), AioLinuxScheduler::stop(), ResourceTest::testConcurrency(), and LocalConditionTest::testNotifyAll().

00057 {
00058     assert(pBoostThread);
00059     boost::thread t;
00060     assert(*pBoostThread != t);
00061     pBoostThread->join();
00062     delete pBoostThread;
00063     pBoostThread = NULL;
00064 }

bool Thread::isStarted (  )  const [inline, inherited]

Returns:
true if start has been called (and subsequent join has not completed)

Reimplemented in AioLinuxScheduler.

Definition at line 71 of file Thread.h.

Referenced by closeImpl(), CacheImpl< PageT, VictimPolicyT >::closeImpl(), AioLinuxScheduler::isStarted(), and TimerThread::stop().

00072     {
00073         return pBoostThread ? true : false;
00074     }

bool Thread::isStopped (  )  const [inline, inherited]

Returns:
opposite of isStarted()

Definition at line 79 of file Thread.h.

00080     {
00081         return !isStarted();
00082     }

boost::thread& Thread::getBoostThread (  )  [inline, inherited]

Accesses the underlying boost::thread, e.g.

for use in a boost::thread_group. This thread must already be started.

Returns:
the underlying boost::thread

Definition at line 90 of file Thread.h.

00091     {
00092         assert(isStarted());
00093         return *pBoostThread;
00094     }

std::string Thread::getName (  )  [inline, inherited]

Definition at line 96 of file Thread.h.

00097     {
00098         return name;
00099     }

void Thread::setName ( std::string const &  s  )  [inline, inherited]

Definition at line 101 of file Thread.h.

00102     {
00103         name = s;
00104     }

bool ClosableObject::isClosed (  )  const [inline, inherited]

Returns:
whether the object has been closed

Definition at line 58 of file ClosableObject.h.

00059     {
00060         return !needsClose;
00061     }

void ClosableObject::close (  )  [inherited]

Closes this object, releasing any unallocated resources.

Reimplemented in CollectExecStream, CorrelationJoinExecStream, LcsClusterAppendExecStream, and LcsClusterReplaceExecStream.

Definition at line 39 of file ClosableObject.cpp.

References ClosableObject::closeImpl(), and ClosableObject::needsClose.

Referenced by CacheImpl< PageT, VictimPolicyT >::allocatePages(), LcsRowScanBaseExecStream::closeImpl(), ExecStreamGraphImpl::closeImpl(), FlatFileBuffer::open(), ClosableObjectDestructor::operator()(), and Segment::~Segment().

00040 {
00041     if (!needsClose) {
00042         return;
00043     }
00044     needsClose = false;
00045     closeImpl();
00046 }

Member Data Documentation

Database& CheckpointThread::database [private]

Definition at line 42 of file CheckpointThread.h.

Referenced by run().

SXMutex CheckpointThread::actionMutex [private]

Definition at line 43 of file CheckpointThread.h.

Referenced by CheckpointThread(), getActionMutex(), and run().

CheckpointType CheckpointThread::checkpointType [private]

Definition at line 44 of file CheckpointThread.h.

Referenced by CheckpointThread(), requestCheckpoint(), and run().

bool CheckpointThread::quit [private]

Definition at line 45 of file CheckpointThread.h.

Referenced by CheckpointThread(), closeImpl(), and run().

boost::thread* Thread::pBoostThread [protected, inherited]

Definition at line 44 of file Thread.h.

Referenced by Thread::join(), Thread::start(), Thread::Thread(), and Thread::~Thread().

bool Thread::bRunning [protected, inherited]

Definition at line 45 of file Thread.h.

Referenced by Thread::afterRun(), Thread::beforeRun(), Thread::Thread(), and Thread::~Thread().

std::string Thread::name [protected, inherited]

Definition at line 46 of file Thread.h.

Referenced by Thread::Thread().

StrictMutex SynchMonitoredObject::mutex [protected, inherited]

Definition at line 38 of file SynchMonitoredObject.h.

Referenced by ParallelExecStreamScheduler::abort(), LogicalTxnLog::checkpoint(), Database::checkpointImpl(), closeImpl(), LogicalTxnLog::commitTxn(), ParallelExecStreamScheduler::executeManager(), ParallelExecStreamScheduler::executeTask(), LogicalTxnLog::getOldestActiveTxnId(), LogicalTxnLog::newLogicalTxn(), ParallelExecStreamScheduler::readStream(), SXMutex::release(), GroupLock::release(), Database::requestCheckpoint(), requestCheckpoint(), LogicalTxnLog::rollbackTxn(), TimerThread::run(), run(), ThreadPoolBase::runPooledThread(), SXMutex::setSchedulingPolicy(), TimerThread::signalImmediate(), ParallelExecStreamScheduler::signalSentinel(), ThreadPoolBase::start(), TimerThread::stop(), ThreadPoolBase::stop(), ParallelExecStreamScheduler::stop(), ThreadPool< RandomAccessRequest >::submitTask(), ParallelExecStreamScheduler::tryExecuteManager(), ParallelExecStreamScheduler::tryExecuteTask(), SXMutex::tryUpgrade(), SXMutex::waitFor(), GroupLock::waitFor(), and Database::writeStats().

LocalCondition SynchMonitoredObject::condition [protected, inherited]

Definition at line 39 of file SynchMonitoredObject.h.

Referenced by ParallelExecStreamScheduler::abort(), Database::checkpointImpl(), closeImpl(), LogicalTxnLog::commitTxnWithGroup(), ParallelExecStreamScheduler::executeTask(), ParallelExecStreamScheduler::readStream(), SXMutex::release(), GroupLock::release(), Database::requestCheckpoint(), requestCheckpoint(), TimerThread::run(), run(), ThreadPoolBase::runPooledThread(), TimerThread::signalImmediate(), TimerThread::stop(), ThreadPoolBase::stop(), ParallelExecStreamScheduler::stop(), ThreadPool< RandomAccessRequest >::submitTask(), ParallelExecStreamScheduler::tryExecuteManager(), ParallelExecStreamScheduler::tryExecuteTask(), SXMutex::waitFor(), and GroupLock::waitFor().

bool ClosableObject::needsClose [protected, inherited]

Definition at line 44 of file ClosableObject.h.

Referenced by SegStreamAllocation::beginWrite(), ExecStreamGraphImpl::clear(), ClosableObject::ClosableObject(), ClosableObject::close(), FlatFileBuffer::open(), ExecStreamGraphImpl::open(), ExecStream::open(), and ClosableObject::~ClosableObject().

The documentation for this class was generated from the following files:
Generated on Mon Jun 22 04:00:28 2009 for Fennel by  doxygen 1.5.1