Hi. I wanted to see this difference. It is somewhat ad hoc. However, It is more effective than it doesn't show it at all.
-- MinGW(win32) -- $ test_fsync Simple write timing: write 3.644000 Compare fsync times on write() and non-write() descriptor: (If the times are similar, fsync() can sync data written on a different descriptor.) write, fsync, close 40.543000 write, close, fsync 47.033000 Compare one o_sync write to two:(o_sync unavailable) open o_dsync, write 0.094000
(fdatasync unavailable) write, fsync, 26.700000 Compare file sync methods with 2 8k writes: open o_dsync, write 0.203000 (fdatasync unavailable) write, fsync, 27.920000 Regards, Hiroshi Saito
test_fsync_patch
Description: Binary data
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