linux - Replacing multiple fdatasync() calls with a single sync() call -


i have application thousands of files being updated. periodically application needs commit changes disk, , calling fdatasync(), takes significant amount of time (minutes). [reducing number of files being written not option me.]

at same time, noticed if ran sync command command line, return faster. documentation seems guarantee pending writes reached disk.

the question is: sync() system call give same (or stronger) durability guarantees multiple fdatasync() calls? if not, there way fsync() multiple file descriptors in 1 call?


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