Re: FUSION-IO io cards - Mailing list pgsql-performance

We have a bunch of their cards, purchased when we were still on 8.1 and were having difficulty with vacuums. (Duh.) They helped out a bunch for that. They're fast, no question about it. Each FusionIO device (they have cards with multiple devices) can do ~100k iops. So that's nifty. 

On the downside, they're also somewhat exotic, in that they need special kernel drivers, so they're not as easy as just buying a bunch of drives. More negatively, they're $$$. And even more negatively, their drivers are inefficient - expect to dedicate a CPU core to doing whatever they need done. 

In the "still undecided" category I'm somewhat worried about their longevity. They say they overprovision the amount of flash so that burnout isn't a problem, and at least it's not like competitors we've seen, which throttle your writes so that you don't burn out as fast. Of course, the only way to tell how long they'll really last is to use them a long time. We're only about 2 years into them so come back to me in 3 years about this. :) Also, while I would say they seem reliable (they have a supercap and succeeded every power-pull test we did) we just recently we've had some issues which appear to be fio driver-related that effectively brought our server down. Fusion thinks its our kernel parameters, but we're unconvinced, given the length of time we've run with the same kernel settings. I'm not yet ready to say these cards are unreliable, but I'm no longer willing to say they're problem-free, either. I would say, if you're going to buy them, make sure you get a support contract. We didn't, and the support we've gotten so far has not been as responsive and I would have expected from such an expensive product.

Overall, I would recommend them. But just realize you're buying the race car of the storage world, which implies 1) you'll go fast, 2) you'll spend $$$, and 3) you'll have interesting problems most other people do not have.