Microsoft has announced a new family of virtual machines called D-Series that offers better memory, CPU and faster I/O. With this Azure joins the club of elite IaaS providers with SSD backed storage.
Customers running I/O intensive workloads like OLTP and NoSQL databases on cloud often find the performance limiting. SSD storage offers better IOPS than the conventional storage that is based on the magnetic medium. According to Scott Guthrie, executive vice president of Microsoft Cloud and Enterprise group, the new D-Series of VMs are 60% faster than the A-Series of VMs. XtremeData, one of the early adopters of the new family of Azure VMs mentioned that they found the VMs to provide high performance and scalability. The new VM sizes are available in two families – general purpose and high performance.
Below is a comparison of the new VM configuration.
AWS, Google, Digital Ocean and ProfitBricks already offer VMs based on SSD. Amazon EC2 was one of the first to support SSD backed VMs. It offers both instance store and persistent block-level storage. Instance store provides temporary storage, which means that the data on an instance store volume, persists only during the life of the associated Amazon EC2 instance. Persistent block-level storage is called Elastic Block Store (EBS) that can store data independent of the life of VM. EBS is also available in Provisioned IOPS (PIOPS) mode that delivers better throughput than the general purpose SSD based EBS.
Google Compute Engine offers two types of persistent disk volumes: standard persistent disks and SSD persistent disks. Unlike Amazon EBS, GCE doesn’t expect the customers to provision the IOPS before hand. The I/O performance of the disk depends on the type of VM and the size of the disk used. High-end VMs with larger disks deliver better performance.
Digital Ocean, the New York based cloud infrastructure startup boasts of an SSD-only cloud that provides customers with high-performance SSD Hard Drives. ProfitBricks is another IaaS provider that offers SSD based persistence.
One important aspect of SSD based VMs on Azure is that they are not persistent. Data stored on these volumes cannot survive the crash or termination of virtual machines. This is different from both Amazon EC2 and Google Compute Engine, which offer persistent SSDs. On Azure, customers have to ensure that the data stored on the SSD disks is constantly backed up to Azure blob storage or other VMs. Customer will realize the power of SSD when running high availability database workloads like SQL Server cluster or MongoDB Replica Set.
Microsoft Azure is aiming for feature parity with Amazon Web Services and with the availability of SSD based VMs, it scored yet another point.