Messages in this thread | | | Date | Mon, 21 Nov 2011 13:47:15 +0100 | From | Andi Kleen <> | Subject | Re: [PATCH 1/8] block: limit default readahead size for small devices |
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On Mon, Nov 21, 2011 at 05:00:04AM -0500, Christoph Hellwig wrote: > On Mon, Nov 21, 2011 at 05:18:20PM +0800, Wu Fengguang wrote: > > Given that the non-rotational attribute is not always reported, we can > > take disk size as a max readahead size hint. This patch uses a formula > > that generates the following concrete limits: > > Given that you mentioned the rotational flag and device size in this > mail, as well as benchmarking with an intel SSD - did you measure > how useful large read ahead sizes still are with highend Flash device > that have extremly high read IOP rates?
The more the IOPs the larger the "window" you need to keep everything going I suspect.
-Andi -- ak@linux.intel.com -- Speaking for myself only.
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