Fix deadlock in DatabaseOrdinary in case of exception while loading tables.

This commit is contained in:
Nikolai Kochetov 2018-12-05 15:46:32 +03:00
parent a451a9282b
commit 715d120ed9
2 changed files with 49 additions and 5 deletions

View File

@ -165,6 +165,7 @@ void DatabaseOrdinary::loadTables(
AtomicStopwatch watch;
std::atomic<size_t> tables_processed {0};
Poco::Event all_tables_processed;
ExceptionHandler exception_handler;
auto task_function = [&](const String & table)
{
@ -186,7 +187,7 @@ void DatabaseOrdinary::loadTables(
for (const auto & filename : file_names)
{
auto task = std::bind(task_function, filename);
auto task = createExceptionHandledJob(std::bind(task_function, filename), exception_handler);
if (thread_pool)
thread_pool->schedule(task);
@ -197,6 +198,8 @@ void DatabaseOrdinary::loadTables(
if (thread_pool)
all_tables_processed.wait();
exception_handler.throwIfException();
/// After all tables was basically initialized, startup them.
startupTables(thread_pool);
}
@ -210,12 +213,18 @@ void DatabaseOrdinary::startupTables(ThreadPool * thread_pool)
std::atomic<size_t> tables_processed {0};
size_t total_tables = tables.size();
Poco::Event all_tables_processed;
ExceptionHandler exception_handler;
if (!total_tables)
return;
auto task_function = [&](const StoragePtr & table)
{
SCOPE_EXIT(
if (++tables_processed == total_tables)
all_tables_processed.set()
);
if ((tables_processed + 1) % PRINT_MESSAGE_EACH_N_TABLES == 0
|| watch.compareAndRestart(PRINT_MESSAGE_EACH_N_SECONDS))
{
@ -224,14 +233,11 @@ void DatabaseOrdinary::startupTables(ThreadPool * thread_pool)
}
table->startup();
if (++tables_processed == total_tables)
all_tables_processed.set();
};
for (const auto & name_storage : tables)
{
auto task = std::bind(task_function, name_storage.second);
auto task = createExceptionHandledJob(std::bind(task_function, name_storage.second), exception_handler);
if (thread_pool)
thread_pool->schedule(task);
@ -241,6 +247,8 @@ void DatabaseOrdinary::startupTables(ThreadPool * thread_pool)
if (thread_pool)
all_tables_processed.wait();
exception_handler.throwIfException();
}

View File

@ -58,3 +58,39 @@ private:
void worker();
};
class ExceptionHandler
{
public:
void setException(std::exception_ptr && exception)
{
std::unique_lock<std::mutex> lock(mutex);
if (!first_exception)
first_exception = std::move(exception);
}
void throwIfException()
{
std::unique_lock<std::mutex> lock(mutex);
if (first_exception)
std::rethrow_exception(first_exception);
}
private:
std::exception_ptr first_exception;
std::mutex mutex;
};
ThreadPool::Job createExceptionHandledJob(ThreadPool::Job job, ExceptionHandler & handler)
{
return [job{std::move(job)}, &handler] ()
{
try
{
job();
}
catch (...)
{
handler.setException(std::current_exception());
}
};
}