[eatonphil]

Did I miss it or is there no call to os.File.Sync(), i.e. fsync, anywhere?

Since you mention etcd/wal:

https://github.com/etcd-io/etcd/blob/v3.3.27/wal/wal.go#L671

https://github.com/etcd-io/etcd/blob/v3.3.27/pkg/fileutil/sy...

[stym06]

I used the bufio flush mechanism https://pkg.go.dev/bufio#Writer.Flush

Thanks for your comment, I'll definitely check it out. It was my first attempt at this. How can I make it better?

[sakras]

Essentially, unless you `fsync`, there's no guarantee that your data will be durably written to disk. This is because the operating system keeps data buffered in in-memory caches, so if the machine crashes you may lose some data. The `fsync` system call forces the data to be flushed from the in-memory OS cache to the disk. As far as I could tell, the Flush you use does not `fsync`.

[stym06]

Thanks for your input @sakras. I'll fix this