How to reduce costs of on demand instances with spot instances

For those who want to reduce costs of on demand instance prices, there is an interesting tip how to do it with spot instances. In general spot instances are sold in form of an auction when there is unused capacity available at cloud provider. Well actually I think only Amazon has it in this form. In longer term it turns out that spot instance costs are somehow at a level of reserved instances, but you don’t need to pay reservation fee upfront. If you want to ensure your instance is not terminated just overbid, give even much higher price than normal on demand price – this is just a maximum you are willing to pay, but the final price will come when clearing price is set, which will be usually much lower. Obviously I wouldn’t recommend this method for mission critical servers.

You can find out more on this subject here:

• Don’t forget Spot Instances on AWS
• On delivering highly available services using spot instances

Would you like to see such pricing model implemented in Cloudorado - cloud computing price comparison engine?