On 09/09/2011 04:52 PM, Nicholas Thomas wrote:
> +/* qemu-nbd has a limit of slightly less than 1M per request. For safety,
> + * transfer at most 512K per request. */
> +#define NBD_MAX_SECTORS 1024
As far as I'm aware, the limit of 1MiB - header size is common to all
NBD servers. I'm not aware of anything at all that'll fail on a 768K
request but succeed in the exact same circumstances on a 512K request.
Again, this is a performance consideration - each request is relatively
slow, so you don't want them to be unnecessarily small.
Yes, it should probably be bumped to 1536 or 2040 (to keep requests
4k-aligned). I wasn't sure about the limit. I've never seen requests
that big anyway.
Paolo
