https://twitter.com/MagicalTuxUntil now we had too much iops and system was having trouble keeping up with the load progression. Switched to a RAID 10 SSD array
We gave them how many M$ yesterday and all it bought us is a 10 disc array?
He probably means a raid level of 10, or more accurately 1-0. Such arrays can be anywhere from 4 to a metric crapload of drives, although 4 is the most common configuration.