________________________________________
From: Nicholas A. Bellinger <nab@xxxxxxxxxxxxxxx>
Sent: Thursday, January 18, 2018 11:58 AM
> Hi Shiraz, Michal & Co,
Hi Nicholas,
> Thanks for the feedback. Comments below.
> A couple of thoughts.
> First, would it be helpful to limit maximum payload size per I/O for
> consumers based on number of iser-target sq hw sges..?
I don't think you need to limit the maximum payload, but instead
initialize the max_wr to be based on the number of supported SGEs
Instead of what is there today:
#define ISERT_QP_MAX_REQ_DTOS (ISCSI_DEF_XMIT_CMDS_MAX + \
ISERT_MAX_TX_MISC_PDUS + \
ISERT_MAX_RX_MISC_PDUS)
Add the maximum number of WQEs per command,
The calculation of number of WQEs per command needs to be something like
"MAX_TRANSFER_SIZE/(numSges*PAGE_SIZE)".
For some devices like ours, breaking the IO into multiple WRs according to supported
number of SGEs doesn't necessarily means performance penalty.
thanks,
Michal
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