On Mon, Oct 26, 2009 at 09:58:05PM +0200, Mertol Ozyoney wrote: > In all 2500 and 6000 series you can assign raid set's to a controller and > that controller becomes the owner of the set.
When I configured all 32-drives on a 6140 array and the expansion chassis, CAM automatically split the drives amongst controllers evenly. > The advantage of 2540 against it's bigger brothers (6140 which is EOL'ed) > and competitors 2540 do use dedicated data paths for cache mirroring just > like higher end unit disks (6180,6580, 6780) improving write performance > significantly. > > Spliting load between controllers can most of the time increase performance, > but you do not need to split in two equal partitions. > > Also do not forget that first tray have dedicated data lines to the > controller so generaly it's wise not to mix those drives with other drives > on other trays. But, if you have an expansion chassis, and create a zpool with drives on the first tray and subsequent trays, what's the difference? You cannot tell zfs which vdev to assign writes to so it seems pointless to balance your pool based on the chassis when reads/writes are potentially spread across all vdevs. > Best regards > Mertol > > > > > Mertol Ozyoney > Storage Practice - Sales Manager > > Sun Microsystems, TR > Istanbul TR > Phone +902123352200 > Mobile +905339310752 > Fax +902123352222 > Email mertol.ozyo...@sun.com > > > > -----Original Message----- > From: zfs-discuss-boun...@opensolaris.org > [mailto:zfs-discuss-boun...@opensolaris.org] On Behalf Of Bob Friesenhahn > Sent: Tuesday, October 13, 2009 10:59 PM > To: Nils Goroll > Cc: zfs-discuss@opensolaris.org > Subject: Re: [zfs-discuss] STK 2540 and Ignore Cache Sync (ICS) > > On Tue, 13 Oct 2009, Nils Goroll wrote: > > > > Regarding my bonus question: I haven't found yet a definite answer if > there > > is a way to read the currently active controller setting. I still assume > that > > the nvsram settings which can be read with > > > > service -d <arrayname> -c read -q nvsram region=0xf2 host=0x00 > > > > do not necessarily reflect the current configuration and that the only way > to > > make sure the controller is running with that configuration is to reset > it. > > I believe that in the STK 2540, the controllers operate Active/Active > except that each controller is Active for half the drives and Standby > for the others. Each controller has a copy of the configuration > information. Whichever one you communicate with is likely required to > mirror the changes to the other. > > In my setup I load-share the fiber channel traffic by assigning six > drives as active on one controller and six drives as active on the > other controller, and the drives are individually exported with a LUN > per drive. I used CAM to do that. MPXIO sees the changes and does > map 1/2 the paths down each FC link for more performance than one FC > link offers. > > Bob > -- > Bob Friesenhahn > bfrie...@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ > GraphicsMagick Maintainer, http://www.GraphicsMagick.org/ > _______________________________________________ > zfs-discuss mailing list > zfs-discuss@opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss > > _______________________________________________ > zfs-discuss mailing list > zfs-discuss@opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss > -- albert chin (ch...@thewrittenword.com) _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
