On Wed, 2004-03-31 at 09:08, Stephen C. Tweedie wrote:
On Tue, 2004-03-30 at 23:21, Jeff Garzik wrote:
For IDE, O_DIRECT and O_SYNC can use special "FUA" commands, which don't return until the data is on the platter.
fsync() is still really nasty, because that can require that we wait on
IO that was submitted by the VM before we knew that there was a
synchronous IO wait coming.
Yes, it gets ugly in a hurry. Jeff, look at the whole thread about the
O_DIRECT read vs buffered write races. I don't think we can use FUA for
fsync or O_SYNC without using it for every write.
We might be able to get away with using it on O_DIRECT.