concurrent_unordered_map 類別 concurrent_unordered_map 類別是一種並行安全容器,可控制 std::pair<const K, _Element_type> 類型項目的不同長度序列。 序列的表示方式導致啟用並行安全附加、項目存取、迭代器存取及迭代器周遊作業。 concurrent_unordered_multimap 類別
事务开启后,应该向Watermark中添加read ts(AddTxn) 关于Watermark的成员std::unordered_map<timestamp_t, int> current_reads_: 其表示RUNNING状态的txn read ts, 由于read ts为last commit ts,所以可能存在多个read ts. 因此current_reads_的value为read ts的数量。 你可能对Watermark.commit_ts_感到疑惑,该成员...
Lock Manager在这里的实现主要是通过维护一个hash table(unordered_map),table中的元素是一个内部结点为获取锁的请求的队列,每个队列中,每个结点都包含是否授予锁与请求的锁的类型 enumclassLockMode{SHARED,EXCLUSIVE,INTENTION_SHARED,INTENTION_EXCLUSIVE,SHARED_INTENTION_EXCLUSIVE};/*** Structure to hold a lock r...
LockManager中的unordered_map<txn_id_t, vector<txn_id_t>> waits_for_代表等待图,键为事务 T(顶点),值为事务 T 在等待解锁的其他事务的集合,二者组成了等待图中的边。 复制voidLockManager::AddEdge(txn_id_tt1,txn_id_tt2){txns_.insert(t1);txns_.insert(t2);auto&neighbors = waits_for_[t1];...
concurrent_unordered_map ClassTheconcurrent_unordered_mapclass is a concurrency-safe container that controls a varying-length sequence of elements of typestd::pair<const K, _Element_type>. The sequence is represented in a way that enables concurrency-safe append, element access, iterator access, an...
#define LOCAL #include<bits/stdc++.h> using namespace std; int main(){ #ifdef LOCAL freopen("data.in","r",stdin); freopen("data.out","w",stdout); #endif // LOCAL int n,t[5],Q; scanf("%d%d%d",&n,&t[0],&t[1],&t[2],&t[3],&t[4],&Q); unordered_map<char,int>v...
For example, you can insert std::unique_ptr objects into concurrent_unordered_set, concurrent_unordered_multiset, concurrent_unordered_map, and concurrent_unordered_multimap objects. You can imagine other resource abstractions, such as network or database connections, that do not allow cop...
一般情况下,这样的结构允许代码通过键值对相关的数据值进行查询。在C++标准库中,这种相关工具有:std::map<>,std::multimap<>, std::unordered_map<>以及std::unordered_multimap<>。查询表的使用与栈和队列不同。栈和队列上,几乎每个操作都会对数据结构进行修改,不是添加一个元素,就是删除一个,而对于查询表来...
gatherUnordered(tasks).unsafePerformSync //> res3: List[Int] = List(1, 2, 3, 4, 5) 7 val sb = new StringBuffer //> sb : StringBuffer = 8 val t1 = Task.fork { Thread.sleep(100); sb.append("a"); Task.now("a")} 9 //> t1 : scalaz.concurrent.Task[String] = scalaz...
How to: Use combinable to Combine SetsDescribes thecombinableclass, as well asconcurrent_vector,concurrent_queue,concurrent_unordered_map, and other parallel containers. Use parallel containers and objects when you require containers that provide thread-safe access to their elements. ...