What disk setup do you use?

[bikedorkseattle]

I wanted to post this in a separate thread since my stack thread was so productive.

What type of disk setup do you find best on your servers for running IPB? Assume you are running web and db on the same box.

SSDs seem to be the future, but the cost is still a bit prohibitive for us. One option I'm looking at is using a soft raid 10 with sata 7.2ks. I'm able to get this with most hosts for an additional $45 with the hosts. Looking at the performance seems to be about half of a 6G SSD. We have a very large photo gallery so the problem is the cost of getting an SSD big enough to accommodate that is quite expensive.

If you were to go a non SSD route what do your recommend? I've read some pretty good arguments against using a hardware raid, and that you'd be better off spending the money on a better processor.

[Grumpy]

I use SSD and mine is frankly too busy to use anything else.

If you have a large space requirement, just plain 7.2k drives may be your only solution at a budget. But if you don't need a lot of space, which I'd expect most forums to. Something like 80~120GB SSD is no more expensive than 1TB drive (SSD is now roughly 1GB/USD vs 7.2k is now roughly 10GB/USD). I also see a lot of hosting companies provide ssds swap of similar to above for no extra charge. Though of course, this isn't that common. Especially large and slow to change companies will still charge zounds for SSDs.
Now, if you try to only get enterprise ssd (which statistically isn't much more reliable than consumer ssd, at least for intel), price sure does jump a lot. Many still don't trust consumer SSDs as much (as I do), so they do often opt for a more reliable enterprise ssd should an ssd become a need.

I've done a heavy soft raid 10 before. It performs okay, but in the case of a failure, the rebuild takes a really long time under soft raid. When pushed to extreme, it does not perform as well as something like soft raid 0 or 1. It will consume a fair amount of CPU if your disks are too slow and causing cpu waits. But when it comes to hardware vs software raid, there's one key thing to consider b4 ruling one better than the other.
Is it a high end raid card with BBU? or a low end?
High end raid card with BBU (which naturally also has write caches) perform very good because of write caches. It's sorta like having a mini-ssd in front of the disks so that it can handle heavy small writes very well. If you look at low end raid card, I personally believe they're worthless piece of crap because soft almost always out does it in performance to price ratio -- like you said, just get a better cpu.

On the question of, how better is ssd on raid 1 than something like 4 disk raid 10 7.2k drives? A freaking lot. sequential write wise, it's not much better, if at all. In random seek and write, it's not even worth comparing b/c we're looking at 75~100 IOPS per disk on 7.2k vs 100k for SSD per disk. Quite literally a 1000 better.

If you're just coming off of a VPS, you most likely don't need an SSD. Though, the point I make with price is, is there a desire for such? :tongue:

[bikedorkseattle]

The problem is our gallery data alone is 100GB, and I anticipate in switching gallery usage will go up substantially since photopost sorta sucks. Would it make sense to run a SSD raid 1 for everything but put gallery data on a raid 1 7.2k drives? Gives us SSD speed for system, db, and site, space to grow for our gallery.

We are actually on a dedicated (AMD Opteron 175) single SATA and a VPS for DB. DB is a huge bottleneck right now but our site is slow in general so I'm really looking at improving that to make it as fast as possible.

I think I'm just lusting over an SSD more then anything :)

[Feld0]

There is virtually no comparison in performance between SSD's and hard drives. A basic Intel SSD will outdo four 15k RPM SAS drives in RAID10 any day of the week without breaking a sweat.

But likewise, there is virtually no comparison between the two as far as cost per GB goes. If you have tons of data outside of the database, in the filesystem, putting it on SSD's doesn't make much sense.

I ended up getting a custom dedicated server built that combines the best of both worlds - two Intel SSD's and two 7.2k RPM Western Digital hard drives. The SSD's and hard drives are both in software RAID1, which provides redundancy and performs admirably without a costly hardware RAID card. cPanel, the OS, all applications, Minecraft servers, and MySQL's databases live on the SSD array; but my /home directory is mapped to the hard drive array. This way, databases respond at blinding speed while an enormous amount of cheap storage is available for everything else. 32 GB of RAM, a hand-tuned MySQL config that uses a huge chunk of it, and a Xeon E3 are the cherry on top. :)

[bikedorkseattle]

Feld0, thanks for sharing your config, that seems like a good option for our gallery intensive site.

[Dmacleo]

my bottleneck seem to be disc speed although it, right now, not a huge issue for me.
running 2 7200 500gb sata3 as raid1 with 500gb drive for backups...when I get off my butt and point backups to it.
raid is from the board built in raid controller (I forget specs now) and the speed difference from no raid to raid1 like that was not noticeable on my end.
if possible ssd is way to go IMHO, faster and less power draw. when possible I will be changing but will be a bit.

[Aussie Cable]

We use SSD in RAID 1 and have 7.2k's for backup

Not sure if that helps or not, but that is what we use.

[maddog107_merged]

4x512gb SSD in RAID5 on an LSI controller. Spent way too much time trying to optimize, at the end of the day my time was worth more then the cost of the disks and the controller.