A SAS Outstanding Xfer_RDY Question.

Elliott, Robert (Server Storage) elliott at hp.com
Mon Jun 30 15:47:01 PDT 2003

* From the T10 Reflector (t10 at t10.org), posted by:
* "Elliott, Robert (Server Storage)" <elliott at hp.com>
I think the mode page is more than enough for this misplaced feature.

First Burst Size is not useful for the low latency environment which SAS
is supposed to be.  SAS COMMAND frames are interlocked, requiring
waiting for an ACK before sending another frame.  There's not much
benefit for the target to send just an ACK after receiving a COMMAND
frame rather than send an ACK followed by an XFER_RDY frame.  It's not
like iSCSI, where the data can be pipelined right behind the command
frame because they are likely to be in transit over a very long
Rob Elliott, elliott at hp.com
Hewlett-Packard Industry Standard Server Storage Advanced Technology
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