On Wed, 21 Sep 2011 08:49:34 -0700 Ira Weiny <[email protected]> wrote:
> On Wed, 21 Sep 2011 07:17:38 -0700 > Hal Rosenstock <[email protected]> wrote: > > > Hi Al, <snip> > > > > > On 0001-Support-ibccquery-congestion-control-query-tool.patch, I'm > > worried about the following: > > + /* XXX: Q3/2010 errata lists first entry offset at 80, but we > > assume > > + * will be updated to 96 once CurrentTimeStamp field is word > > aligned. > > + * In addition, assume max 13 log events instead of 16. Due to > > + * errata changes increasing size of CA log event, 16 log > > events is > > + * no longer possible to fit in max MAD size. > > + */ > > > > As far as the 13 v. 16 entries, this appears correct to me (MAD size) > > but I'm concerned about changing the offset from 80 to 96 for better > > alignment as this is putting the cart before the horse a little as > > since these changes have not been finalized AFAIK at the IBTA. > > Yes, it is a bit premature. I have submitted the above alignment as a comment > to the IBTA but as you say it is not published. Most importantly the > miss-alignment breaks the convention of the spec. So I don't think the IBTA > will reject the comment. > > Second the current alignment breaks libibmad. So it would be a lot more code > to support the miss-alignment and would probably have to be changed anyway. > > > > > Also, would you comment on what testing has been done with this ? > > > > Right, the real question is what does current hardware do? > > We have been unable to determine if any of the vendors support the errata > fully or specifically the miss-aligned CurrentTimeStamp. When I asked the > vendors I got concrete answers back, so we proceeded with trying to reverse ^^^ I meant to say "no concrete" answers here. Sorry, Ira > engineer it. Right now the query succeeds, that is all we know. > > Perhaps someone on the list can help us find out? :-D > > In the meantime we wanted to get comments on the patches. > > Ira > > > -- Hal > > > > > Al > > > > > > -- > > > Albert Chu > > > [email protected] > > > Computer Scientist > > > High Performance Systems Division > > > Lawrence Livermore National Laboratory > > > > > > > > -- > > 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 > > > -- > Ira Weiny > Member of Technical Staff > Lawrence Livermore National Lab > 925-423-8008 > [email protected] -- Ira Weiny Member of Technical Staff Lawrence Livermore National Lab 925-423-8008 [email protected] -- 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
