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|
// @file threadedtests.cpp - Tests for threaded code
//
/**
* Copyright (C) 2008 10gen Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the GNU Affero General Public License in all respects
* for all of the code used other than as permitted herein. If you modify
* file(s) with this exception, you may extend this exception to your
* version of the file(s), but you are not obligated to do so. If you do not
* wish to do so, delete this exception statement from your version. If you
* delete this exception statement from all source files in the program,
* then also delete it in the license file.
*/
#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kCommand
#include "mongo/platform/basic.h"
#include <boost/version.hpp>
#include <iostream>
#include "mongo/config.h"
#include "mongo/db/client.h"
#include "mongo/db/concurrency/d_concurrency.h"
#include "mongo/db/concurrency/lock_state.h"
#include "mongo/db/operation_context_impl.h"
#include "mongo/dbtests/dbtests.h"
#include "mongo/platform/atomic_word.h"
#include "mongo/platform/bits.h"
#include "mongo/stdx/functional.h"
#include "mongo/stdx/thread.h"
#include "mongo/util/concurrency/mvar.h"
#include "mongo/util/concurrency/old_thread_pool.h"
#include "mongo/util/concurrency/rwlock.h"
#include "mongo/util/concurrency/synchronization.h"
#include "mongo/util/concurrency/old_thread_pool.h"
#include "mongo/util/concurrency/ticketholder.h"
#include "mongo/util/log.h"
#include "mongo/util/timer.h"
namespace ThreadedTests {
using std::unique_ptr;
using std::cout;
using std::endl;
using std::string;
template <int nthreads_param=10>
class ThreadedTest {
public:
virtual void setup() {} //optional
virtual void subthread(int remaining) = 0; // each thread whatever test work you want done
virtual void validate() = 0; // after work is done
static const int nthreads = nthreads_param;
void run() {
setup();
launch_subthreads(nthreads);
validate();
}
virtual ~ThreadedTest() {}; // not necessary, but makes compilers happy
private:
void launch_subthreads(int remaining) {
if (!remaining)
return;
stdx::thread athread(stdx::bind(&ThreadedTest::subthread, this, remaining));
launch_subthreads(remaining - 1);
athread.join();
}
};
#ifdef MONGO_PLATFORM_32
// Avoid OOM on Linux-32 by using fewer threads
const int nthr=45;
#else
const int nthr=135;
#endif
class MongoMutexTest : public ThreadedTest<nthr> {
#if defined(MONGO_CONFIG_DEBUG_BUILD)
enum { N = 2000 };
#else
enum { N = 4000/*0*/ };
#endif
ProgressMeter pm;
public:
MongoMutexTest() : pm(N * nthreads) {
}
void run() {
Timer t;
cout << "MongoMutexTest N:" << N << endl;
ThreadedTest<nthr>::run();
cout << "MongoMutexTest " << t.millis() << "ms" << endl;
}
private:
virtual void subthread(int tnumber) {
Client::initThread("mongomutextest");
OperationContextImpl txn;
sleepmillis(0);
for( int i = 0; i < N; i++ ) {
int x = std::rand();
bool sometimes = (x % 15 == 0);
if( i % 7 == 0 ) {
Lock::GlobalRead r(txn.lockState()); // nested test
Lock::GlobalRead r2(txn.lockState());
}
else if( i % 7 == 1 ) {
Lock::GlobalRead r(txn.lockState());
ASSERT(txn.lockState()->isReadLocked());
}
else if( i % 7 == 4 &&
tnumber == 1 /*only one upgrader legal*/ ) {
Lock::GlobalWrite w(txn.lockState());
ASSERT( txn.lockState()->isW() );
if( i % 7 == 2 ) {
Lock::TempRelease t(txn.lockState());
}
}
else if( i % 7 == 2 ) {
Lock::GlobalWrite w(txn.lockState());
ASSERT( txn.lockState()->isW() );
if( sometimes ) {
Lock::TempRelease t(txn.lockState());
}
}
else if( i % 7 == 3 ) {
Lock::GlobalWrite w(txn.lockState());
{
Lock::TempRelease t(txn.lockState());
}
Lock::GlobalRead r(txn.lockState());
ASSERT( txn.lockState()->isW() );
if( sometimes ) {
Lock::TempRelease t(txn.lockState());
}
}
else if( i % 7 == 5 ) {
{
ScopedTransaction scopedXact(&txn, MODE_IS);
Lock::DBLock r(txn.lockState(), "foo", MODE_S);
}
{
ScopedTransaction scopedXact(&txn, MODE_IS);
Lock::DBLock r(txn.lockState(), "bar", MODE_S);
}
}
else if( i % 7 == 6 ) {
if( i > N/2 ) {
int q = i % 11;
if( q == 0 ) {
ScopedTransaction scopedXact(&txn, MODE_IS);
Lock::DBLock r(txn.lockState(), "foo", MODE_S);
ASSERT(txn.lockState()->isDbLockedForMode("foo", MODE_S));
Lock::DBLock r2(txn.lockState(), "foo", MODE_S);
ASSERT(txn.lockState()->isDbLockedForMode("foo", MODE_S));
Lock::DBLock r3(txn.lockState(), "local", MODE_S);
ASSERT(txn.lockState()->isDbLockedForMode("foo", MODE_S));
ASSERT(txn.lockState()->isDbLockedForMode("local", MODE_S));
}
else if( q == 1 ) {
// test locking local only -- with no preceding lock
{
ScopedTransaction scopedXact(&txn, MODE_IS);
Lock::DBLock x(txn.lockState(), "local", MODE_S);
}
{
ScopedTransaction scopedXact(&txn, MODE_IX);
Lock::DBLock x(txn.lockState(), "local", MODE_X);
// No actual writing here, so no WriteUnitOfWork
if( sometimes ) {
Lock::TempRelease t(txn.lockState());
}
}
} else if( q == 1 ) {
{
ScopedTransaction scopedXact(&txn, MODE_IS);
Lock::DBLock x(txn.lockState(), "admin", MODE_S);
}
{
ScopedTransaction scopedXact(&txn, MODE_IX);
Lock::DBLock x(txn.lockState(), "admin", MODE_X);
}
}
else if( q == 3 ) {
ScopedTransaction scopedXact(&txn, MODE_IX);
Lock::DBLock x(txn.lockState(), "foo", MODE_X);
Lock::DBLock y(txn.lockState(), "admin", MODE_S);
}
else if( q == 4 ) {
ScopedTransaction scopedXact(&txn, MODE_IS);
Lock::DBLock x(txn.lockState(), "foo2", MODE_S);
Lock::DBLock y(txn.lockState(), "admin", MODE_S);
}
else {
ScopedTransaction scopedXact(&txn, MODE_IX);
Lock::DBLock w(txn.lockState(), "foo", MODE_X);
{
Lock::TempRelease t(txn.lockState());
}
Lock::DBLock r2(txn.lockState(), "foo", MODE_S);
Lock::DBLock r3(txn.lockState(), "local", MODE_S);
}
}
else {
ScopedTransaction scopedXact(&txn, MODE_IS);
Lock::DBLock r(txn.lockState(), "foo", MODE_S);
Lock::DBLock r2(txn.lockState(), "foo", MODE_S);
Lock::DBLock r3(txn.lockState(), "local", MODE_S);
}
}
pm.hit();
}
}
virtual void validate() {
{
MMAPV1LockerImpl ls;
Lock::GlobalWrite w(&ls);
}
{
MMAPV1LockerImpl ls;
Lock::GlobalRead r(&ls);
}
}
};
template <typename _AtomicUInt>
class IsAtomicWordAtomic : public ThreadedTest<> {
static const int iterations = 1000000;
typedef typename _AtomicUInt::WordType WordType;
_AtomicUInt target;
void subthread(int) {
for(int i=0; i < iterations; i++) {
target.fetchAndAdd(WordType(1));
}
}
void validate() {
ASSERT_EQUALS(target.load() , unsigned(nthreads * iterations));
_AtomicUInt u;
ASSERT_EQUALS(0u, u.load());
ASSERT_EQUALS(0u, u.fetchAndAdd(WordType(1)));
ASSERT_EQUALS(2u, u.addAndFetch(WordType(1)));
ASSERT_EQUALS(2u, u.fetchAndSubtract(WordType(1)));
ASSERT_EQUALS(0u, u.subtractAndFetch(WordType(1)));
ASSERT_EQUALS(0u, u.load());
u.fetchAndAdd(WordType(1));
ASSERT_GREATER_THAN(u.load(), WordType(0));
u.fetchAndSubtract(WordType(1));
ASSERT_NOT_GREATER_THAN(u.load(), WordType(0));
}
};
class MVarTest : public ThreadedTest<> {
static const int iterations = 10000;
MVar<int> target;
public:
MVarTest() : target(0) {}
void subthread(int) {
for(int i=0; i < iterations; i++) {
int val = target.take();
#if BOOST_VERSION >= 103500
//increase chances of catching failure
stdx::this_thread::yield();
#endif
target.put(val+1);
}
}
void validate() {
ASSERT_EQUALS(target.take() , nthreads * iterations);
}
};
class ThreadPoolTest {
static const unsigned iterations = 10000;
static const unsigned nThreads = 8;
AtomicUInt32 counter;
void increment(unsigned n) {
for (unsigned i=0; i<n; i++) {
counter.fetchAndAdd(1);
}
}
public:
void run() {
OldThreadPool tp(nThreads);
for (unsigned i=0; i < iterations; i++) {
tp.schedule(&ThreadPoolTest::increment, this, 2);
}
tp.join();
ASSERT_EQUALS(counter.load(), iterations * 2);
}
};
class RWLockTest1 {
public:
void run() {
RWLock lk( "eliot" );
{
rwlock r( lk , true , 1000 );
}
}
};
class RWLockTest2 {
public:
static void worker1( RWLockRecursiveNongreedy * lk , AtomicUInt32 * x ) {
x->fetchAndAdd(1); // 1
RWLockRecursiveNongreedy::Exclusive b(*lk);
x->fetchAndAdd(1); // 2
}
static void worker2( RWLockRecursiveNongreedy * lk , AtomicUInt32 * x ) {
RWLockRecursiveNongreedy::Shared c(*lk);
x->fetchAndAdd(1);
}
void run() {
/**
* note: this test will deadlock if the code breaks
*/
RWLockRecursiveNongreedy lk( "eliot2" , 120 * 1000 );
cout << "RWLock impl: " << lk.implType() << endl;
unique_ptr<RWLockRecursiveNongreedy::Shared> a( new RWLockRecursiveNongreedy::Shared(lk) );
AtomicUInt32 x1(0);
cout << "A : " << &x1 << endl;
stdx::thread t1( stdx::bind( worker1 , &lk , &x1 ) );
while ( ! x1.load() );
verify( x1.load() == 1 );
sleepmillis( 500 );
verify( x1.load() == 1 );
AtomicUInt32 x2(0);
stdx::thread t2( stdx::bind( worker2, &lk , &x2 ) );
t2.join();
verify( x2.load() == 1 );
a.reset();
for ( int i=0; i<2000; i++ ) {
if ( x1.load() == 2 )
break;
sleepmillis(1);
}
verify( x1.load() == 2 );
t1.join();
}
};
class RWLockTest3 {
public:
static void worker2( RWLockRecursiveNongreedy * lk , AtomicUInt32 * x ) {
verify( ! lk->__lock_try(0) );
RWLockRecursiveNongreedy::Shared c( *lk );
x->fetchAndAdd(1);
}
void run() {
/**
* note: this test will deadlock if the code breaks
*/
RWLockRecursiveNongreedy lk( "eliot2" , 120 * 1000 );
unique_ptr<RWLockRecursiveNongreedy::Shared> a( new RWLockRecursiveNongreedy::Shared( lk ) );
AtomicUInt32 x2(0);
stdx::thread t2( stdx::bind( worker2, &lk , &x2 ) );
t2.join();
verify( x2.load() == 1 );
a.reset();
}
};
class RWLockTest4 {
public:
#if defined(__linux__) || defined(__APPLE__)
static void worker1( pthread_rwlock_t * lk , AtomicUInt32 * x ) {
x->fetchAndAdd(1); // 1
cout << "lock b try" << endl;
while ( 1 ) {
if ( pthread_rwlock_trywrlock( lk ) == 0 )
break;
sleepmillis(10);
}
cout << "lock b got" << endl;
x->fetchAndAdd(1); // 2
pthread_rwlock_unlock( lk );
}
static void worker2( pthread_rwlock_t * lk , AtomicUInt32 * x ) {
cout << "lock c try" << endl;
pthread_rwlock_rdlock( lk );
x->fetchAndAdd(1);
cout << "lock c got" << endl;
pthread_rwlock_unlock( lk );
}
#endif
void run() {
/**
* note: this test will deadlock if the code breaks
*/
#if defined(__linux__) || defined(__APPLE__)
// create
pthread_rwlock_t lk;
verify( pthread_rwlock_init( &lk , 0 ) == 0 );
// read lock
verify( pthread_rwlock_rdlock( &lk ) == 0 );
AtomicUInt32 x1(0);
stdx::thread t1( stdx::bind( worker1 , &lk , &x1 ) );
while ( ! x1.load() );
verify( x1.load() == 1 );
sleepmillis( 500 );
verify( x1.load() == 1 );
AtomicUInt32 x2(0);
stdx::thread t2( stdx::bind( worker2, &lk , &x2 ) );
t2.join();
verify( x2.load() == 1 );
pthread_rwlock_unlock( &lk );
for ( int i=0; i<2000; i++ ) {
if ( x1.load() == 2 )
break;
sleepmillis(1);
}
verify( x1.load() == 2 );
t1.join();
#endif
}
};
// we don't use upgrade so that part is not important currently but the other aspects of this test are
// interesting; it would be nice to do analogous tests for SimpleRWLock and QLock
class UpgradableTest : public ThreadedTest<7> {
RWLock m;
public:
UpgradableTest() : m("utest") {}
private:
virtual void validate() { }
virtual void subthread(int x) {
Client::initThread("utest");
/* r = get a read lock
R = get a read lock and we expect it to be fast
u = get upgradable
U = get upgradable and we expect it to be fast
w = get a write lock
*/
// /-- verify upgrade can be done instantly while in a read lock already
// | /-- verify upgrade acquisition isn't greedy
// | | /-- verify writes aren't greedy while in upgradable (or are they?)
// v v v
const char *what = " RURuRwR";
sleepmillis(100*x);
int Z = 1;
LOG(Z) << x << ' ' << what[x] << " request" << endl;
char ch = what[x];
switch( ch ) {
case 'w':
{
m.lock();
LOG(Z) << x << " w got" << endl;
sleepmillis(100);
LOG(Z) << x << " w unlock" << endl;
m.unlock();
}
break;
case 'u':
case 'U':
{
Timer t;
RWLock::Upgradable u(m);
LOG(Z) << x << ' ' << ch << " got" << endl;
if( ch == 'U' ) {
#if defined(NTDDI_VERSION) && defined(NTDDI_WIN7) && (NTDDI_VERSION >= NTDDI_WIN7)
// SRW locks are neither fair nor FIFO, as per docs
if( t.millis() > 2000 ) {
#else
if( t.millis() > 20 ) {
#endif
DEV {
// a debug buildbot might be slow, try to avoid false positives
mongo::unittest::log() <<
"warning lock upgrade was slow " << t.millis() << endl;
}
else {
mongo::unittest::log() <<
"assertion failure: lock upgrade was too slow: " <<
t.millis() << endl;
ASSERT( false );
}
}
}
sleepsecs(1);
LOG(Z) << x << ' ' << ch << " unlock" << endl;
}
break;
case 'r':
case 'R':
{
Timer t;
m.lock_shared();
LOG(Z) << x << ' ' << ch << " got " << endl;
if( what[x] == 'R' ) {
if( t.millis() > 15 ) {
// commented out for less chatter, we aren't using upgradeable anyway right now:
// log() << x << " info: when in upgradable, write locks are still greedy on this platform" << endl;
}
}
sleepmillis(200);
LOG(Z) << x << ' ' << ch << " unlock" << endl;
m.unlock_shared();
}
break;
default:
ASSERT(false);
}
}
};
void sleepalittle() {
Timer t;
while( 1 ) {
stdx::this_thread::yield();
if( t.micros() > 8 )
break;
}
}
int once;
/* This test is to see how long it takes to get a lock after there has been contention -- the OS
will need to reschedule us. if a spinlock, it will be fast of course, but these aren't spin locks.
Experimenting with different # of threads would be a good idea.
*/
template <class whichmutex, class scoped>
class Slack : public ThreadedTest<17> {
public:
Slack() : m("slack") {
k = 0;
done = false;
a = b = 0;
locks = 0;
}
private:
whichmutex m;
char pad1[128];
unsigned a, b;
char pad2[128];
unsigned locks;
char pad3[128];
volatile int k;
virtual void validate() {
if( once++ == 0 ) {
// <= 1.35 we use a different rwmutex impl so worth noting
cout << "Boost version : " << BOOST_VERSION << endl;
}
cout << typeid(whichmutex).name() <<
" Slack useful work fraction: " << ((double)a)/b << " locks:" << locks << endl;
}
void watch() {
while( 1 ) {
b++;
//__sync_synchronize();
if( k ) {
a++;
}
sleepmillis(0);
if( done )
break;
}
}
volatile bool done;
virtual void subthread(int x) {
if( x == 1 ) {
watch();
return;
}
Timer t;
unsigned lks = 0;
while( 1 ) {
scoped lk(m);
k = 1;
// not very long, we'd like to simulate about 100K locks per second
sleepalittle();
lks++;
if( done || t.millis() > 1500 ) {
locks += lks;
k = 0;
break;
}
k = 0;
//__sync_synchronize();
}
done = true;
}
};
class CondSlack : public ThreadedTest<17> {
Notification n;
public:
CondSlack() {
k = 0;
done = false;
a = b = 0;
locks = 0;
}
private:
unsigned a, b;
virtual void validate() {
cout << "CondSlack useful work fraction: " << ((double)a)/b << " locks:" << locks << endl;
}
unsigned locks;
volatile int k;
void watch() {
while( 1 ) {
b++;
if( k ) {
a++;
}
sleepmillis(0);
if( done )
break;
}
}
volatile bool done;
virtual void subthread(int x) {
if( x == 1 ) {
n.notifyOne();
watch();
return;
}
Timer t;
while( 1 ) {
n.waitToBeNotified();
verify( k == 0 );
k = 1;
// not very long, we'd like to simulate about 100K locks per second
sleepalittle();
k = 0;
locks++;
n.notifyOne();
if( done || t.millis() > 1500 )
break;
}
done = true;
}
};
const int WriteLocksAreGreedy_ThreadCount = 3;
class WriteLocksAreGreedy : public ThreadedTest<WriteLocksAreGreedy_ThreadCount> {
public:
WriteLocksAreGreedy() : m("gtest"), _barrier(WriteLocksAreGreedy_ThreadCount) {}
private:
RWLock m;
boost::barrier _barrier;
virtual void validate() { }
virtual void subthread(int x) {
_barrier.wait();
int Z = 0;
Client::initThread("utest");
if( x == 1 ) {
LOG(Z) << mongo::curTimeMillis64() % 10000 << " 1" << endl;
rwlock_shared lk(m);
sleepmillis(400);
LOG(Z) << mongo::curTimeMillis64() % 10000 << " 1x" << endl;
}
if( x == 2 ) {
sleepmillis(100);
LOG(Z) << mongo::curTimeMillis64() % 10000 << " 2" << endl;
rwlock lk(m, true);
LOG(Z) << mongo::curTimeMillis64() % 10000 << " 2x" << endl;
}
if( x == 3 ) {
sleepmillis(200);
Timer t;
LOG(Z) << mongo::curTimeMillis64() % 10000 << " 3" << endl;
rwlock_shared lk(m);
LOG(Z) << mongo::curTimeMillis64() % 10000 << " 3x" << endl;
LOG(Z) << t.millis() << endl;
ASSERT( t.millis() > 50 );
}
}
};
// Tests waiting on the TicketHolder by running many more threads than can fit into the "hotel", but only
// max _nRooms threads should ever get in at once
class TicketHolderWaits : public ThreadedTest<10> {
static const int checkIns = 1000;
static const int rooms = 3;
public:
TicketHolderWaits() : _hotel( rooms ), _tickets( _hotel._nRooms ) {}
private:
class Hotel {
public:
Hotel( int nRooms ) : _nRooms( nRooms ), _checkedIn( 0 ), _maxRooms( 0 ) {}
void checkIn(){
stdx::lock_guard<stdx::mutex> lk( _frontDesk );
_checkedIn++;
verify( _checkedIn <= _nRooms );
if( _checkedIn > _maxRooms ) _maxRooms = _checkedIn;
}
void checkOut(){
stdx::lock_guard<stdx::mutex> lk( _frontDesk );
_checkedIn--;
verify( _checkedIn >= 0 );
}
mongo::mutex _frontDesk;
int _nRooms;
int _checkedIn;
int _maxRooms;
};
Hotel _hotel;
TicketHolder _tickets;
virtual void subthread(int x) {
string threadName = ( str::stream() << "ticketHolder" << x );
Client::initThread( threadName.c_str() );
for( int i = 0; i < checkIns; i++ ){
_tickets.waitForTicket();
TicketHolderReleaser whenDone( &_tickets );
_hotel.checkIn();
sleepalittle();
if( i == checkIns - 1 ) sleepsecs( 2 );
_hotel.checkOut();
if( ( i % ( checkIns / 10 ) ) == 0 )
mongo::unittest::log() << "checked in " << i << " times..." << endl;
}
}
virtual void validate() {
// This should always be true, assuming that it takes < 1 sec for the hardware to process a check-out/check-in
// Time for test is then ~ #threads / _nRooms * 2 seconds
verify( _hotel._maxRooms == _hotel._nRooms );
}
};
class All : public Suite {
public:
All() : Suite( "threading" ) { }
void setupTests() {
add< WriteLocksAreGreedy >();
// Slack is a test to see how long it takes for another thread to pick up
// and begin work after another relinquishes the lock. e.g. a spin lock
// would have very little slack.
add< Slack<SimpleMutex,SimpleMutex::scoped_lock> >();
add< Slack<SimpleRWLock,SimpleRWLock::Exclusive> >();
add< CondSlack >();
add< UpgradableTest >();
add< IsAtomicWordAtomic<AtomicUInt32> >();
add< IsAtomicWordAtomic<AtomicUInt64> >();
add< MVarTest >();
add< ThreadPoolTest >();
add< RWLockTest1 >();
add< RWLockTest2 >();
add< RWLockTest3 >();
add< RWLockTest4 >();
add< MongoMutexTest >();
add< TicketHolderWaits >();
}
};
SuiteInstance<All> myall;
}
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