Cheap SSD arrays for Continuous Integration
The need for iop/s
I think that every sysdamin has this need. It is like "I have a need - the need for speed". So basically when I see 400 operations per second as upper limit on some SATA drives the I cry very loudly.
But bussiness can't always provide RAID10 array of 4x240GB Intel SSD drives / $4000.
I faced this problem lately. While improving environment performance for continuous integration I noticed how drastically we have this need for iop/s on every Jenkins and Selenium nodes.
So we have this bleeding-edge-storage which has couple of enterprise class SSDs but honestly I didn't want to sacrifice those holy part of our infrastructure for some ephemeral work.
I just wanted some drives which would provide me w/about 15-20k iop/s. Simple, cheap SSD drives.
So I found, that our servers actually have a free drive slots inside. Unused. Just waiting to be fulfilled with something. Think local storage :D
And this was it. What about buying desktop - class SSD drives?
Trim issue?
It is not an issue. Just make sure you've got fstrim running and remember to trim on all filesystem layers(!)
So... what kind of drives?
According to this The best price to longevity ratio will give you Kingston HyperX drives ($100 each 240GB drive). So basically you can set up RAID1 for $200 or RAID10 for $400.
Of course this is just for some temporary data. Those kind of arrays should't be there for crucial datastores. And of course - remember about capacity planning. When I see 600TB written as the moment in time when the drive will be dead I can basically say, that $200 RAID array will need to be replaced in 18 months. Wow - this is really nice lifetime for this at this price. So I actualy created 2xRAID10 arrays (240GB Kingston HyperX drives) what gave me 2x0,5TB in RAID10 / local storage for $1000. And I'm gonna replace this in about 1,5 year (maybe still as a subject of warranty).
Great deal imo. If I did want to but enterprise class disks (like Intel) for this purpose I would have to pay 8*$1000 and that is a horrible amount of goldies.
Summing this up - CI (Jenkins, Selenium, others) + local storage on cheap SSD drives = <3