On Wed, 2006-03-01 at 16:29 +0100, Jens Axboe wrote: > Strictly speaking, the clustering bit is unrelated. I seem to recall > Gerard years ago talking about some sym chips that did not like > clustering, hence it was disabled. Yes, I remember that too ... I've never been able to find out which chip, though ... the scripts all seem happily coded for variable size sg segments. However, given the new way 2.6 does memory allocations, ENABLE_CLUSTERING will probably make quite a difference to the size of the sg list ... since we try to allocate contiguous pages, physical merging becomes much more of a possibility (I think I last measured it at around 30% of all SG tables, as opposed to <1% with the old allocation method). James - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
