CoreData问题:需要对persistentCoordina加锁,但不知道加在哪些代码合适。不同的NSManagedObjectContext,但公用同一个NSPersistentCoordinator,是否允许两个线程同时进行读操作,而不对NSPersistentCoordinator进行lock?还是不管读和写,都需要对lock coordinator?
之前虽然是多线程操作coredata,没加lock,但是由于工作线程并没有很频繁的操作数据库,因此没出问题。但是现在我的工作线程需要2分钟一次对数据库进行查询、更新的逻辑,所以程序有时可以运行,有时executeFetch时候会卡死,报的错误是deadlock,死锁!很奇怪,我这时候根本就没对数据库加过锁啊!
是因为,coordinator对所有的操作,都会序列化(serialize operations),然后多线程操作coredata时候,我代码里面没有lock coordinator,所以就出现了deadlock的错误?
多谢大家的关注或回答啊!
Once every two minutes, how long does it take? Does each operation take seconds?
If it takes seconds, add a lock to the thread yourself. If it takes longer, consider caching the data into memory, etc.
First of all, it is recommended not to operate the same NSPersistentStoreCoordinator in multiple threads.
Multi-threaded read and write operations on the same NSPersistentStoreCoordinator may indeed cause deadlock. Therefore, it is recommended to lock NSPersistentStoreCoordinator for every write operation to avoid thinking