HashTable::~HashTable has a sleep

HashTable::~HashTable() {

    // Use unlocked clear for the destructor, avoids lock inversions on VBucket

    // delete

    clear_UNLOCKED(true);

    // Wait for any outstanding visitors to finish.

    while (visitors > 0) {

#ifdef _MSC_VER

        Sleep(1);

#else

        usleep(100);

#endif

    }

    delete []mutexes;

}