Core Blimey! Azure moving from physical to virtual cores

Updated Microsoft's revealed that virtual machines in its Azure cloud will soon be defined by virtual rather than physical cores.

Microsoft says the change “is a key architectural change in our VMs that enables us to unlock the full potential of the latest processors.” The post then names Intel's Broadwell E5-2673 v4 2.3 as the creature that will power some new instance types.

Which is a little odd as Intel doesn't list that model among the E5 v4 family. The Register has therefore asked Intel to confirm the CPU's status. If this is a Microsoft-only Xeon it's not unusual: Oracle gets its very own Xeons and Intel is known to do custom jobs for other large customers.

Back to Azure, which Microsoft says will put its new virtual cores to work in new instance types.

The forthcoming for Dv3 instances are pitched at “general purpose workloads” and Microsoft promises that when they arrive “later this year” they will “be priced up to 28% lower than Dv2 Series VMs, matching the comparable AWS instance prices.”

Another new instance type, the Ev3, are suggested as ideal for “memory optimized workloads”. Each instance will therefore offer up to 432 gigabytes of memory.

Redmond's also outlining some cloudy price cuts. Its L Series VMs are being cut “60% to 69% … to match recent price changes from AWS.”

The cost of the Dv2 instance type is also being discounted to the price you'll pay once the Dv3s go live.

This is an odd announcement for a couple of reasons. Firstly, the big clouds often chase each other to the bottom on price, but the cut to the L Series comes just a few weeks after it was launched and at up to 69 per cent is very deep, even by the standards of cloudy competition. And then there's the discounts on the Dv2 series, which Microsoft could probably have avoided if it kept schtum about the forthcoming Dv3.

The Register suspects Redmond saw customers heading in another direction for certain workloads and decided to put down a marker so that customers can commit with confidence.

Whatever the reason, this cloud stuff is fun: when's the last time server vendors chased each other's prices in public ahead of a launch? ®

Updated to add on April 12

Intel's been in touch to tell us that Microsoft is indeed using a custom Xeon. An earlier version of this story suggested the Broadwell E5-2673 v4 2.3 Microsoft is using may have had 64 cores. Intel's pointed out that's not the case. To clarify, Microsoft's post says it will use the CPU to create virtual machines with up to 64 virtual cores.