Variants of the FSYNC story have been going on for decades now. The framing varies, but typically somebody is benchmarking IO (often in the context of database benchmarking) and discovers a curious variance by OS.
On NVMes I wonder whether this really matters, but it's a serious issue on spinning disks: do you really need to flush everything to the disk (and interrupt more efficient access patterns)?
On NVMes I wonder whether this really matters, but it's a serious issue on spinning disks: do you really need to flush everything to the disk (and interrupt more efficient access patterns)?