Not sure of your space requirements, but I'd think a RAID 10 of 8x or more Samsung 840 Pro 256/512 GB would be the best value. Using a simple mirror won't get you the reliability that you want since heavy writing will burn the drives out over time, and if you're writing the exact same content to both drives, they could likely fail at the same time. Regardless of the underlying hardware you should still follow best practices for provisioning disks, and raid 10 is the way to go. I don't know what your budget is though. Anyway, mirrored SSD will probably work fine, but I'd avoid using just two drives for the reasons above. I'd suggest at least testing RAID 5 or something else to spread the load around. Personally, I think the ideal configuration would be a RAID 10 of at least 8 disks plus 1 hot spare. The Samsung 840 Pro 256 GB are frequently $200 on sale at Newegg. YMMV but they are amazing drives.
On Fri, May 10, 2013 at 11:25 AM, David Boreham <david_list@xxxxxxxxxxx> wrote:
On 5/10/2013 9:19 AM, Matt Brock wrote:I've never looked at SLC drives in the past few years and don't know anyone who uses them these days.
After googling this for a while, it seems that High Endurance MLC is only starting to rival SLC for endurance and write performance in the very latest, cutting-edge hardware. In general, though, it seems it would be fair to say that SLCs are still a better bet for databases than MLC?
Could you post some specific drive models please ? HP probably doesn't make the drives, and it really helps to know what devices you're using since they are not nearly as generic in behavior and features as magnetic drives.
The number and capacity of drives is small in this instance, and the price difference between the two for HP SSDs isn't very wide, so cost isn't really an issue. We just want to use whichever is better for the database.
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