Method KeyValueStoreSQLite

fdbserver/KeyValueStoreSQLite.actor.cpp:2133–2182

static int vfs_registered = 0;

KeyValueStoreSQLite::KeyValueStoreSQLite(std::string const& filename,
                                         UID id,
                                         KeyValueStoreType storeType,
                                         bool checkChecksums,
                                         bool checkIntegrity)
  : type(storeType), logID(id), filename(filename), readThreads(CoroThreadPool::createThreadPool()),
    writeThread(CoroThreadPool::createThreadPool()), readsRequested(0), writesRequested(0), writesComplete(0),
    diskBytesUsed(0), freeListPages(0) {
	TraceEvent(SevDebug, "KeyValueStoreSQLiteCreate").detail("Filename", filename);

	stopOnErr = stopOnError(this);

#if SQLITE_THREADSAFE == 0
	ASSERT(writeThread->isCoro());
#endif

	if (!vfs_registered && writeThread->isCoro())
		if (sqlite3_vfs_register(vfsAsync(), true) != SQLITE_OK)
			ASSERT(false);

	// The DB file should not already be open
	ASSERT(!vfsAsyncIsOpen(filename));
	ASSERT(!vfsAsyncIsOpen(filename + "-wal"));

	readCursors.resize(SERVER_KNOBS->SQLITE_READER_THREADS); //< number of read threads

	sqlite3_soft_heap_limit64(SERVER_KNOBS->SOFT_HEAP_LIMIT); // SOMEDAY: Is this a performance issue?  Should we drop
	                                                          // the cache sizes for individual threads?
	TaskPriority taskId = g_network->getCurrentTask();
	g_network->setCurrentTask(TaskPriority::DiskWrite);
	// Note: the below is actually a coroutine and not a thread.
	writeThread->addThread(new Writer(this,
	                                  type == KeyValueStoreType::SSD_BTREE_V2,
	                                  checkChecksums,
	                                  checkIntegrity,
	                                  writesComplete,
	                                  springCleaningStats,
	                                  diskBytesUsed,
	                                  freeListPages,
	                                  id,
	                                  &readCursors),
	                       "fdb-sqlite-wr");
	g_network->setCurrentTask(taskId);
	auto p = new Writer::InitAction();
	auto f = p->result.getFuture();
	writeThread->post(p);
	starting = startReadThreadsWhen(this, f, logID);
	cleaning = cleanPeriodically(this);
	logging = logPeriodically(this);
}
KeyValueStoreSQLite::~KeyValueStoreSQLite() {
	// printf("dbf=%lld bytes, wal=%lld bytes\n", getFileSize((filename+".fdb").c_str()),
	// getFileSize((filename+".fdb-wal").c_str()));