2011/1/7 Jeremy Chadwick <free...@jdc.parodius.com>: > On Fri, Jan 07, 2011 at 12:29:17PM +1100, Jean-Yves Avenard wrote: >> On 6 January 2011 22:26, Chris Forgeron <cforge...@acsi.ca> wrote: >> > You know, these days I'm not as happy with SSD's for ZIL. I may blog about >> > some of the speed results I've been getting over the last 6mo-1yr that >> > I've been running them with ZFS. I think people should be using hardware >> > RAM drives. You can get old Gigabyte i-RAM drives with 4 gig of memory for >> > the cost of a 60 gig SSD, and it will trounce the SSD for speed. >> > >> > I'd put your SSD to L2ARC (cache). >> >> Where do you find those though. >> >> I've looked and looked and all references I could find was that >> battery-powered RAM card that Sun used in their test setup, but it's >> not publicly available.. > > DDRdrive: > http://www.ddrdrive.com/ > http://www.engadget.com/2009/05/05/ddrdrives-ram-based-ssd-is-snappy-costly/ > > ACard ANS-9010: > http://techreport.com/articles.x/16255 > > GC-RAMDISK (i-RAM) products: > http://us.test.giga-byte.com/Products/Storage/Default.aspx > > Be aware these products are absurdly expensive for what they offer (the > cost isn't justified), not to mention in some cases a bottleneck is > imposed by use of a SATA-150 interface. I'm also not sure if all of > them offer BBU capability. > > In some respects you might be better off just buying more RAM for your > system and making md(4) memory disks that are used by L2ARC (cache). > I've mentioned this in the past (specifically "back in the days" when > the ARC piece of ZFS on FreeBSD was causing havok, and asked if one > could work around the complexity by using L2ARC with md(4) drives > instead). >
Once you have got extra RAM, why not just reserve it directly to ARC (via vm.kmem_size[_max] and vfs.zfs.arc_max)? Markiyan. > I tried this, but couldn't get rc.d/mdconfig2 to do what I wanted on > startup WRT the aforementioned. > > -- > | Jeremy Chadwick j...@parodius.com | > | Parodius Networking http://www.parodius.com/ | > | UNIX Systems Administrator Mountain View, CA, USA | > | Making life hard for others since 1977. PGP 4BD6C0CB | > > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org" > _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"