Le 19/12/2012 22:38, Dilger, Andreas a écrit : > On 2012-12-19, at 11:22, "Allen, Benjamin > S"<[email protected]<mailto:[email protected]>> wrote: > > Hi Jason, > > 2. Having two paths to your storage should speed things up. I'm guessing > you'd have more than one LUN on the array, > so you could do something as simple as splitting the LUNs between the two > paths, or use round robin to balance the > traffic between the two paths, etc. > > Using round-robin is not a good idea. This will not increase bandwidth > (which is already constrained by the disk and bus) but on some RAID > controllers > will cause severe performance impact. >
I could confirm dell rack disk doesn't support round robin but you define a prefered controller for each raid volume like this [root@oss-locean ~]# multipath -ll LOCEAN_OST5 (3690b11c0000154a40000069a50b86cfb) dm-7 DELL,MD36xxf [size=22T][features=3 queue_if_no_path pg_init_retries 50][hwhandler=1 rdac][rw] \_ round-robin 0 [prio=100][active] \_ 8:0:0:5 sdn 8:208 [active][ready] \_ round-robin 0 [prio=0][enabled] \_ 7:0:0:5 sdg 8:96 [active][ghost] LOCEAN_OST4 (3690b11c0000154b50000072350b86892) dm-6 DELL,MD36xxf [size=22T][features=3 queue_if_no_path pg_init_retries 50][hwhandler=1 rdac][rw] \_ round-robin 0 [prio=100][active] \_ 7:0:0:4 sdf 8:80 [active][ready] \_ round-robin 0 [prio=0][enabled] \_ 8:0:0:4 sdm 8:192 [active][ghost] LOCEAN_OST3 (3690b11c0000154a40000069750b86cc5) dm-5 DELL,MD36xxf [size=22T][features=3 queue_if_no_path pg_init_retries 50][hwhandler=1 rdac][rw] \_ round-robin 0 [prio=100][active] \_ 8:0:0:3 sdl 8:176 [active][ready] \_ round-robin 0 [prio=0][enabled] \_ 7:0:0:3 sde 8:64 [active][ghost] LOCEAN_OST2 (3690b11c0000154b50000072050b86851) dm-4 DELL,MD36xxf [size=22T][features=3 queue_if_no_path pg_init_retries 50][hwhandler=1 rdac][rw] \_ round-robin 0 [prio=100][active] \_ 7:0:0:2 sdd 8:48 [active][ready] \_ round-robin 0 [prio=0][enabled] \_ 8:0:0:2 sdk 8:160 [active][ghost] LOCEAN_OST1 (3690b11c0000154a40000069450b86c79) dm-3 DELL,MD36xxf [size=22T][features=3 queue_if_no_path pg_init_retries 50][hwhandler=1 rdac][rw] \_ round-robin 0 [prio=100][active] \_ 8:0:0:1 sdj 8:144 [active][ready] \_ round-robin 0 [prio=0][enabled] \_ 7:0:0:1 sdc 8:32 [active][ghost] LOCEAN_OST0 (3690b11c0000154b50000071d50b86052) dm-2 DELL,MD36xxf [size=22T][features=3 queue_if_no_path pg_init_retries 50][hwhandler=1 rdac][rw] \_ round-robin 0 [prio=100][active] \_ 7:0:0:0 sdb 8:16 [active][ready] \_ round-robin 0 [prio=0][enabled] \_ 8:0:0:0 sdi 8:128 [active][ghost] > Cheers, Andreas -- Weill Philippe - Administrateur Systeme et Reseaux CNRS/UPMC/IPSL LATMOS (UMR 8190) Tour 45/46 3e Etage B302 - 4 Place Jussieu - 75252 Paris Cedex 05 - FRANCE Email:[email protected] | tel:+33 0144274759 Fax:+33 0144273776 _______________________________________________ Lustre-discuss mailing list [email protected] http://lists.lustre.org/mailman/listinfo/lustre-discuss
