Re: [PATCH] blk queue io tracing support

[Nathan Scott]

On Wed, Aug 31, 2005 at 02:33:10PM +1000, Nathan Scott wrote:
> ...
> On an unrelated note, are there any known issues with using epoll
> on relayfs file descriptors?  I'm having a few troubles, and just
> wondering if its me doing something silly, or if its known to not
> work...?  Symptoms of the problem are epoll continually reaching
> its timeout with no modified fds found (when I know the inode has
> modified trace buffers attached) ...

Actually, poll(2) seems to have the same behaviour with a simpler
test case (i.e. no epoll, & with just one fd being polled) - if I
read(2) from it every few thousand usec (using the blktrace tool)
it sees new data, but if I poll, it never reports the descriptor
as changed (this is a 2.6.13 kernel with the relayfs patches from
-mm patched into it and Jens' blktrace patch generating the data
that I'm attempting to poll).

cheers.

-- 
Nathan
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/