On Tue, 13 Nov 2007, Alan Hodgson wrote:
OK, I'll bite. Name one RAID controller that gives better write
performance in RAID 6 than it does in RAID 10, and post the benchmarks.
I'll grant a theoretical reliability edge to RAID 6 (although actual
implementations are a lot more iffy), but not performance.
Ok, Areca ARC1261ML. Note that results were similar for an 8 drive RAID6 vs 8
drive RAID10, but I don't have those bonnie results any longer.
Version 1.03 ------Sequential Output------ --Sequential Input- --Random-
-Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP
14xRAID6 63G 73967 99 455162 58 164543 23 77637 99 438570 31 912.2 1
------Sequential Create------ --------Random Create--------
-Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
16 12815 63 +++++ +++ 13041 61 12846 67 +++++ +++ 12871 59
Version 1.03 ------Sequential Output------ --Sequential Input- --Random-
-Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP
14xRAID10 63G 63968 92 246143 68 140634 30 77722 99 510904 36 607.8 0
------Sequential Create------ --------Random Create--------
-Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
16 6655 16 +++++ +++ 5755 12 7259 17 +++++ +++ 5550 12
--
Jeff Frost, Owner <jeff@xxxxxxxxxxxxxxxxxxxxxx>
Frost Consulting, LLC http://www.frostconsultingllc.com/
Phone: 650-780-7908 FAX: 650-649-1954
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