Amazon today launched a new web service – EBS, the Elastic Block Store (yes I also first read it as ‘Elastic Book Store’) for EC2. EBS provides persistent storage for EC2 computing instances, and the service is public today and available to all customers after a period of alpha testing with some users.
Previously EC2 instances were able to access temporary storage as part of the compute instance, or persistent storage only on S3 – the Amazon online storage service. The difference between EBS and S3 is that EBS allows block-level access, so that it can be mounted just like any other local storage device from within EC2 and can be accessed across servers and between instances. S3 is accessed as a web service, so performance for latency sensitive applications was never optimal (such as running a database store). EBS provides a much higher level of performance comparable to high-grade local storage in terms of both access times and availability.
Persistant block-level storage for EC2 is perhaps long overdue, as one of the criticisms of EC2 when it first launched was the inability to run a fast data store across snapshots, which made running databases or other data-intensive applications slightly more complicated. Services such as RightScale have built products around helping developers scale and manage MySQL instances on EC2. Other cloud-based computing services such as Mosso or virtual servers from providers such as MediaTemple have had persistent storage options, although what Amazon have developed with the combination of EC2, S3 and now EBS is a tiered approach which provides more flexibility to developers.
Read the rest of this entry at TechCrunchIT.