The scsi_device structure seems to be carrying around a lot of baggage. Assuming the object needs to be present on the SCSI fast path then making it smaller will help in fitting one or several of them in cache lines. Now the effort to use xarrays is helping, but only in the order 32 bytes at the moment. Currently we have pointers to the standard inquiry response and several VPD pages with more VPD pages to come, I suspect. So what about having a secondary scsi_device object (with a more descriptive name) for all those parts of the currect scsi_device object that aren't needed for the fast path? The secondary object could be created in scsi_alloc_sdev() and pointed to by the primary object (and vice versa). Then adding more context info (e.g. more VPD pages) will not burden the fast path. sizeof(struct scsi_device)=1976 bytes! Comments? Doug Gilbert
