What makes a modern commodity cluster?

Question

Would would be the most cost effective way of implementing a terabyte distributed memory cache using commodity hardware these days? What would class as a piece of commodity hardware?

Answer 1

Commodity hardware is considered hardware that

• Is off the shelf (nothing custom)
• Is available in substantially similar version from many manufacturers.

There are many motherboards that can hold 8 or 16 GB of RAM. Fewer server motherboards can hold 32 and even 64GB.

But they fit the definition of commodity, therefore can be made into very large clusters for a very large sum of money.

Note, however, that in many access patterns a striped RAID HD array doesn't go much slower than a gigabit ethernet link - so a RAM cluster might not have significant improvement (except in latency) depending on how you're actually using it.