Amazon is trying to cure cloud punters of buyer's remorse by making it easier for them to chop and change the instances they've acquired from its hulking cloud.
The EC2 Reserved Instance Modification feature was announced by Amazon on Friday and will let admins swap out reserved instances for other models according to a sizing scheme designed by the company.
Reserved Instances let people rent servers from Amazon at a big discount, though they need to fork out a hefty upfront fee to unlock them.
One of the problems with the instances is that once you've bought them you can't re-size them, which is unpleasant if the type of job you're running on them changes over the one or three-year period you've booked the server for.
With Friday's free upgrade, Amazon Web Services users can now shuffle their instances, swapping out, say, an m1.large instance for four m1.small ones, and vice versa, and paying the same price.
"With today's launch you can take advantage of the pricing and capacity benefits of Reserved Instances even as you change from one EC2 instance type to another," the company wrote.
One can only shuffle within groups of instances, which are put together according to platform, type, region, tenancy, offering type, and end date. This means a particularly diverse spread of reserved instances will still be difficult to swap out for others, bur fairly homogeneous stacks should get more flexibility.
Admins should bear in mind that they cannot cancel or change a pending modification request after they've submitted it, according to an AWS FAQ.
This upgrade follows a deep price cut to the reserve instances technology in March, which saw prices fall for some instances by as much as 27.7 per cent. ®