On Thu, Sep 15, 2016 at 01:33:20PM +0100, Alex Bligh wrote: > At an implementation level that is going to be a little difficult > for some NBD servers, e.g. ones that fork() a different process per > connection. There is in general no IPC to speak of between server > instances. Such servers would thus be unsafe with more than one > connection if FLUSH is in use. > > I believe such servers include the reference server where there is > process per connection (albeit possibly with several threads). > > Even single process servers (including mine - gonbdserver) would > require logic to pair up multiple connections to the same > device.
Why? If you only send the completion after your I/O syscall returned your are fine if fsync comes from a difference process, no matter if you're using direct or buffered I/O underneath. -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
