Pricing of AWS RDS [closed]

Question

I am considering moving a Magento site's DB to Amazon's RDS due to the slow read/write speeds of the current host's shared DB cluster. Other hosted sites at the same place with no DB requirement load amazingly fast, so CPU and memory wise I believe the host is well powered.

Will this effectively have an impact of Magento's performance?

If I calculate the costs correctly it will at least cost $79.20 a month. This is based on the smallest instance available ($0.11*24h*30d). On top comes the traffic increased the costs. Is my interpretation of the price guide correct?

Is the latency using an external DB dramatically higher than an internal (same network) DB?

Thank you.

Answer 1

Is the latency using an external DB dramatically higher than an internal (same network) DB?

Yes, it is, and it's very noticeable in environments with lots of requests per second.

You should try to keep your db and web server in the same datacenter if you want high performance, and it might be cheaper for you to just get your own dedicated server and host your magento there instead of complicating things by keeping your web server in one location and then setting up RDS.

Answer 2

Amazon support confirmed that it would cost that much (+$80),

...if I needed the instance running for 24 hours a day during a month

Did they assume that a website only needs its main DB during certain times a day...?

Answer 3

Your figure seems to be about right compared to the 2 Multi-AZ RDS instances I currently run when I look at the bills for June & July. I run one Small Multi-AZ and one Large Multi-AZ so they run $0.22 and $0.88 per hour respectively. The only other calculation to include is the provisioned storage space which for me is $0.20/GB and we have 20GB provisioned and then the I/O requests are charged $0.10 per 1 million. So far those extra charges haven't totaled up to be any amount to be concerned with.

Now for latency, I can't be of much assistance as for the most part I have a dozen EC2 instances talking with the RDS instances; however, I do have my VPS outside the Amazon cloud utilizing the RDS instance to handle storing data for Puppet which I use to configure my EC2 instances. It's configured to do async updates using a message queue so latency isn't a problem but I've never had a problem reaching it.