Douglas McNaught wrote:
"Xin Zhao" <uszhaoxin@xxxxxxxxx> writes:
3. Does sys_close() have to be blocked until all data and metadata
are committed? If not, sys_close() may give application an illusion
that the file is successfully written, which can cause the application
to take subsequent operation. However, data flush could be failed. In
this case, file system seems to mislead the application. Is this true?
If so, any solutions?
The fsync() call is the way to make sure written data has hit the
disk. close() doesn't guarantee that.
-Doug
You should also make sure, if you care about data recovery after a power
outage, that you have either disabled the write cache on your drives or
have a working write barrier. Without this, fsync will move the data
from the page cache to the disk's write cache where it is up to the
drive firmware to write it back to permanent, safe storage on the disk
platter.
ric
-
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
