On Tue, 15 Jan 2008, Chad Walstrom wrote: > softRAID is a viable solution, so don't discount it until you've seen > how your system performs with it. If you have a sufficiently quick > machine with good I/O and plenty of RAM, your overhead for softRAID > might not even be noticed. What I suggest is to watch the performance > of your server resources for a while. If you find that your CPU gets > pegged while pushing data to disk (writes), you might want to upgrade to > hardware raid. (Cacti and Munin make some nice graphs for these > things.) We have a quadcore CPU and we aren't doing a lot of disk-intensive work yet, so the effect of the software RAID is not noticeable. > My favorite SATA RAID controllers are the 3Ware Escalades. I would stay > away from Promise controllers if at all possible. I don't know how the > Adaptec controllers perform, but in all cases you're going to pay an > exceptional chunk of change to get hardware RAID. You'll easily spend > between $350-800 depending upon the number of drives you wish to > support. The two 500 GB disks we are using cost only $250 together. It sounds like hardware RAID controllers are very overpriced. Seriously, with those prices, if the software RAID was impacting on performance, I might go for a faster CPU or dual CPU system instead of buying a RAID controller. > If this is a high-availability server, you may want to invest in the > "battery" module for the card as well, which keeps your write > transactions alive in the event of a power failure. (You might not need > this if your UPS gives sufficient warning to the system to tell it to > shut down cleanly.) That's between $50-200 depending upon the vendor of > the RAID card. That is a good reminder. I want to put a UPS on this system and I haven't done so yet. Mike