Messages in this thread | | | Date | Wed, 31 Aug 2005 10:07:45 +0200 | From | Jens Axboe <> | Subject | Re: A problem about DIRECT IO on ext3 |
| |
On Mon, Aug 29 2005, Erik Mouw wrote: > There are four prerequisites for direct IO: > - the file needs to be opened with O_DIRECT > - the buffer needs to be page aligned (hint: use getpagesize() instead > of assuming that a page is 4k > - reads and writes need to happen *in* multiples of the soft block size > - reads and writes need to happen *at* multiples of the soft block size
Actually, the buffer only needs to be hard block size aligned, same goes for the chunk size used for reads/writes.
-- Jens Axboe
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |