site_archiver@lists.apple.com Delivered-To: darwin-dev@lists.apple.com I know that it hurts performance but correctness is always at odds with the desire for speed. That is correct. However one does not always need to call F_FULLFSYNC -- it should only be called for the critical pieces of data that need it. That is, most writes can just be issued normally (no fsync even). Only when you need to write the header for your transaction to be complete would you need to issue the F_FULLFSYNC fcntl. That is a very good way to put it. The unfortunate thing is that most of the time it's ok. It's only when it matters that you'll find out that you can lose data. --dominic _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.appl... I know this is a comparison of Apples and Oranges. I guess I was just looking for a reality check on this seemingly large difference in performance. I suppose that boils down to the fact that it really does take a long time to get the data onto the platter. So, in other words, we've gotten very used to the speed of the cached write, without really thinking too hard about the data safety issues. This email sent to site_archiver@lists.apple.com