Hi Laurence, On Thu, 2016-04-07 at 17:15 -0400, Laurence Oberman wrote: > Hello > > I have been testing the SRP initiator code to an LIO array here and > part of the testing requires me to set the max_sectors_kb size to get > 4k I/O's. > This has been due to me having to debug various sg_map issues. > > Linux srptest 4.5.0 #2 SMP Thu Apr 7 16:14:38 EDT 2016 x86_64 x86_64 > x86_64 GNU/Linux > This kernel has the scan patch from Hannes, as well as the "[PATCH] > IB/mlx5: Expose correct max_sge_rd limit" patch. > However, I also tested with vanilla 4.5.0 as well and its the same > issue. > > For some reason I cannot change the max_sectors_kb size on 4.5.0 here. > > I chatted with Ewan about it as well and he reminded me about Martins > changes so wondering if that's playing into this. > > Take /dev/sdb as an example > > [root@srptest queue]# sg_inq --p 0xb0 /dev/sdb > VPD INQUIRY: Block limits page (SBC) > Maximum compare and write length: 1 blocks > Optimal transfer length granularity: 256 blocks > Maximum transfer length: 256 blocks > Optimal transfer length: 768 blocks > Maximum prefetch, xdread, xdwrite transfer length: 0 blocks > Just curious what target backend this is with..? Specifically the optimal transfer length granularity and optimal transfer length may be reported by underlying backend device (eg: IBLOCK) in spc_emulate_evpd_b0(). What does 'head /sys/kernel/config/target/core/$HBA/$DEV/attrib/*' of the backend device in question look like..? -- To unsubscribe from this list: 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
