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Magento & Amazon RDS

mcainc asked
Hey guys,

We have a Magento shop with some dedicated hardware that we use for both the web application and database. What I'm considering doing is keeping our web application on our own hardware but offloading the database to Amazon RDS.

Even with local replication and daily backups, I'm worried about losing data in the event of some failure. Compound this by the fact that we were just looking through some old database backups and found out that a lot were corrupted. Definitely scared me straight.

So my question is, does anyone think this could create a huge performance hit? I know EC2 to RDS would be ideal but we have a lot invested in hardware and need to continue using it for the time being.

Beyond that, the only other concern I have is the availability of it. I'm a little confused at the pricing and know that most of the time our database runs relatively low on resources... we do maybe 50-100 transactions per day and use very little CPU. However, on new product launches we can do over 1000+ transactions in a 1 or 2 hour period.

My biggest concern is that I don't want the RDS instance I select to hit a ceiling and create issues when spikes like this occur.

Am I misunderstanding something? Can our RDS spike into just about any level of CPU usage without affecting performance (and only increasing my bill)?

Hopefully that makes sense! Thank you for your time!
Watch Question

When you launch an RDS, you select the instance class your RDS uses. The instance class defines how much memory, cpu and storage is allocated to your RDS.
An RDS instance does not grow automatically beyond the limits you put it in.
You can therefore run a small/standard instance most of the time, manually upgrade to a large before the launch, and downgrade back after the launch fever subsides. Each upgrade and downgrade will require a reboot and downtime of 2-3 minutes.
RDS comes without commitment, so if you can allocate a server for tests, the RDS tests will cost you less than the daily cost of coffee in your office.
Coming back to this open question.
I would like to note that you biggest problem will be the latency between your datacenter and RDS.
If your servers are located anywhere near AWS datacenters, then select the availability zone closest to you. Otherwise do some testing to see if latency is indeed an issue.