如果我将数据块存储在Linux PAGE_SIZE的1 / n或磁盘块大小中，mmap（）可以保证崩溃时的数据完整性吗？

Question

I need to design a system with data persistent and fast reload, which is implemented with mmap() . But systems using mmap() for persistence often lost data integrity on system crash, like single node MongoDB.

What I have is a very flat data structure to store: data are chunked into 1024 sized blocks, no dependency between blocks. Blocks are randomly and heavily accessed and updated during the server uptime.

Answer 1

You can use msync to flush mmapped data to disk.

See http://linux.die.net/man/2/msync .