Comment 16 for bug 709392

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Stefan Bader (smb) wrote :

Hi Joseph, it depends on how you define write operation. If it is the dd, then yes. For the single write requests, which you see in the tcpdump, no. That is the v3 semantics. Which means write with unstable, the server returns before it is actually written to disk. But the commit request which follows each write will only complete (commit reply) when all previous writes are on disk (which in the dumps I see can only be one). When the client sends the write request with FILE_SYNC, the reply to the write request itself will be delayed until the data is on the disk of the server. So doing it with unstable writes and commits for each of them is behaving the same way from the applications point of view. But you send twice as many tcp packets.