Hi Shiraz & Co, Thanks for the feedback. On Mon, 2018-01-22 at 17:49 +0000, Saleem, Shiraz wrote: > > Subject: Re: SQ overflow seen running isert traffic with high block sizes > > > > > > First, would it be helpful to limit maximum payload size per I/O for consumers > > based on number of iser-target sq hw sges..? > > > Assuming data is not able to be fast registered as if virtually contiguous; > artificially limiting the data size might not be the best solution. > > But max SGEs does need to be exposed higher. Somewhere in the stack, > there might need to be multiple WRs submitted or data copied. > Sagi..? > > diff --git a/drivers/target/iscsi/iscsi_target_configfs.c > > b/drivers/target/iscsi/iscsi_target_configf > > index 0ebc481..d8a4cc5 100644 > > --- a/drivers/target/iscsi/iscsi_target_configfs.c > > +++ b/drivers/target/iscsi/iscsi_target_configfs.c > > @@ -1553,6 +1553,7 @@ static void lio_release_cmd(struct se_cmd *se_cmd) > > .module = THIS_MODULE, > > .name = "iscsi", > > .node_acl_size = sizeof(struct iscsi_node_acl), > > + .max_data_sg_nents = 32, /* 32 * PAGE_SIZE = MAXIMUM > > TRANSFER LENGTH */ > > .get_fabric_name = iscsi_get_fabric_name, > > .tpg_get_wwn = lio_tpg_get_endpoint_wwn, > > .tpg_get_tag = lio_tpg_get_tag, > > > > BTW, this is helping the SQ overflow issue. Thanks for confirming as a possible work-around. For reference, what is i40iw's max_send_sg reporting..? Is max_data_sg_nents=32 + 4k pages = 128K the largest MAX TRANSFER LENGTH to avoid consistent SQ overflow as-is with i40iw..? -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
