On Tue, February 9, 2010 10:16 am, Tom Evans wrote: > On Tue, Feb 9, 2010 at 3:01 PM, Dan Langille <[email protected]> wrote: >> >> On Tue, February 9, 2010 9:09 am, Tom Evans wrote: >>> On Tue, Feb 9, 2010 at 1:45 PM, Dan Langille <[email protected]> wrote: >>> One thing to point out about using a PM like this: you won't get >>> fantastic bandwidth out of it. For my needs (home storage server), >>> this really doesn't matter, I just want oodles of online storage, with >>> redundancy and reliability. >> >> >> A PM? Â What's that? >> >> Yes, my priority is reliable storage. Â Speed is secondary. >> >> What bandwidth are you getting? >> > > PM = Port Multiplier > > I'm getting disk speed, as I only have one device behind the PM > currently (just making sure it works properly :). The limits are that > the link from siis to the PM is SATA (3Gb/s, 375MB/s), and the siis > sits on a PCIe 1x bus (2Gb/s, 250 MB/s), so the bandwidth from that is > shared amongst the up-to 5 disks behind the PM. > > Writing from /dev/zero to the pool, I get around 120MB/s. Reading from > the pool, and writing to /dev/null, I get around 170 MB/s. >
That leads me to conclude that a number of SATA cards is better than a port multiplier. But the impression I'm getting is that few of these work well with FreeBSD. Which is odd... I thought these cards would merely present the HDD to the hardware and no diver was required. As opposed to RAID cards for which OS-specific drivers are required. -- Dan Langille -- http://langille.org/ _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "[email protected]"
