RE: I/O and db_file_multiblock_read

From: Kevin Closson <kevinc_at_polyserve.com>
Date: Mon, 11 Dec 2006 15:13:04 -0800
Message-ID: <5D2570CAFC98974F9B6A759D1C74BAD001C3377E@ex2.ms.polyserve.com>

 >>>I'm still thinking that the data was coming from array cache

>>>though, but I may have tangled up service requests for i/o
>>>with the blocking requested by dd, and that may not be
>>>identical in all the layers down to the rust.

yeah, I'm with you, Mark...it is such an astonishingly small datafile it is cachable in a wide variety of places...to include what representation it has in the 8MB track buffers there is on all the involved drives...and I don't think we've lokoed at whether this is even direct I/O.

What I don't want to see happen is some carry-away notion that larger I/O requests are slower... yes, sometimes man bites dog :-)

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Received on Mon Dec 11 2006 - 17:13:04 CST

RE: I/O and db_file_multiblock_read_count