On Thu, Jul 26, 2012 at 10:38 AM, "Xavier R. Guérin" <[email protected]> wrote: > is there any overhead associated with using GIDs?
yes, every packet is 40 bytes longer. > man ibv_post_recv tells me that the GRH is written into the first 40 bytes of > the receive buffer for UD QPs. Is that behavior only restricted to UD QPs, or > should I plan the presence of this headers when using RC QPs ? 40 bytes of UD receive buffers are used for the GRH if it is present, or skipped if it isn't present. For RC/UC/XRC there is no difference at the transport level. That's why the man page only mentions UD. - R. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
