Is Amazon EC Redis an effective caching solution or not?

Question

As you may have noticed Amazon has announced a new feature for its own ElasticCache product, which is supporting Redis.

We are currently using one EC2 instance for our Redis (just queuing for now) and we've decided to use Redis for other upcoming features such as commenting system, discussion, real-time messaging, real-time user tracking and analytics, etc.

We don't mind to run more and bigger EC2 instances, but should we invest in ElasticCache (Redis) and move into it from the beginning now that we haven't started yet or it's too soon to see the results, benchmarks, and downside? Or it's even limited in some prospectives compare to having your own Redis on your own instances?

Update 1:

Let me to be detailed of what we are going to do with Redis. Probably using queuing as we have been doing it by Resque. Not sure if ElasticCache let us do any Pub/Sub but if it does we would like to do that as well. And of course atomic and high-level operations.

Update2:

There is a new video by Senior Product Manger of Amazon Elastic Cache posted a week ago that happened during AWS reInvent Conference. Because it is new he talks about Redis too!

http://www.youtube.com/watch?v=odMmdPBV8hM

Answer 1

I would say that if Redis is an effective caching solution for you, then ElasticCache will work for you - you're simply paying AWS to manage the back end and plumbing for you. Performance may be marginally slower - you have to have a DNS lookup for requests, vs having redis running in a VPC where you can access a private IP address directly - but even accessing it from an EC2 instance should resolve the public DNS name to the internal private IP. And of course you can launch your EC node in your VPC.

There are some complications when running a memcached cluster - you will need to use the amazon client to make sure your code connects to the correct node - but I do not believe as of Dec 2013 that this is needed for redis.

If you're implementing a queue on top of redis, have you looked at SQS to see if it will work for you?