Re: scsipi: physio split the request

[mlelstv%serpens.de@localhost (Michael van Elst)]

jnemeth%cue.bc.ca@localhost (John Nemeth) writes:

>On Dec 27,  6:49pm, Michael van Elst wrote:
>} So far that's mostly a problem with software raid and modern tape I/O.

>     Wouldn't hardware RAID also benefit from bigger buffers?
>Although, I suppose a battery backed cache be used to workaround
>small transfer sizes.

The transfer size currently limits I/O of stripes because it is split
over all stripe units (drives). A hardware controller does this internally
and isn't affected by MAXPHYS.

Of course larger transfers would also mitigate the overhead for each I/O
operation, but we already do several Gigabyte/s with 64k transfers and
filesystem I/O tends to be even smaller.

-- 
-- 
                                Michael van Elst
Internet: mlelstv%serpens.de@localhost
                                "A potential Snark may lurk in every tree."