----- "Harry Putnam" <rea...@newsguy.com> skrev: > Erik Trimble <erik.trim...@oracle.com> writes: > > >> Do you think it would be a problem having a second sata card in a > PCI > >> slot? That would be 8 sata ports in all, since the A-open AK86 > >> motherboard has 2 built in. Or should I swap out the 2prt for the > 4 > >> prt. I really only need 2 more prts currently, but would be nice > to > >> have a couple still open for the future. > >> > > Your PCI bus bandwidth is shared, so it doesn't matter if you use 3 > x > > 2port cards, or 2 x 4port cards (or, in your case, 1x2port + > > 1x4port). Performance is going to be virtually identical. > > Thanks. > So performance with drop as number of drives increases?
Performance is likely to drop with the number of PCI cards on the same bridge. Some motherboards have multiple PCI bridges, but mostly on more expensive server boards (those with PCI-X etc). Performance will probably be limited to the (theoretical) 133/266MB/s plus overhead with more PCI cards. I'd say get an 8-port card to get the best out of it. I would guess your motherboard supports 66MHz, since that came in PCI 2.1 (from wikipedia PCI 2.1, released on June 1, 1995, allows for 66 MHz signaling at 3.3 volt signal voltage (peak transfer rate of 533 MB/s), but at 33 MHz both 5 volt and 3.3 volt signal voltages are still allowed. It also added transaction latency limits to the specification.[7]). roy _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
