The following article goes through best practices for setting up an Ignision Server for iOS development for upwards of 20 users per servervarious use cases.
MacPro Server with 2.7GHz 12-core and 64GB of RAM
Samsung 860 EVO 1TB SSD
ORICO 9548RU3 4 bay 3.5" SATA RAID Hard Drive Enclosure
NewerTech AdaptaDrive 2.5" to 3.5" Drive Converter Bracket
Expected User Experience:
MS Office Users: For a deployment where users are primarily running MS Office applications and doing some web-browsing without video or audio streaming, this server could hold up to 60 concurrent users.
iOS Developers: For a deployment where users are primarily running the iOS Simulator and also compiling code in xCode, this server could hold up to 30 concurrent users.
Creative Cloud Users: For a deployment where users are primarily running Photoshop and InDesign (or Illustrator), this server could hold up to 40 concurrent users.
How-To Guide for iOS Development:
We recommend the hardware above as the Samsung EVO SSD's are very stable, fast, and affordable. The drive enclosure will give you the ability to create a RAID5 (hardware) from those SSDs and export them to the MacPro as a single drive, thus removing the need for SoftRAID (such as AppleRAID). The brackets are of course so the SSDs fit the 3.5" enclosures. If you find that those SSDs aren't large enough, you are able to load that enclosure up with drives as big as 6TB a piece.