Source: infoq.com
Azure Ultra Disk Storage Is Now Generally Available
Microsoft has announced the general availability of Azure Ultra Disk Storage, a new managed disk offering engineered to deliver high throughput, high IOPS, and sub-millisecond latency for the most demanding Azure Virtual Machine and container workloads. The announcement was made via an official Microsoft Azure blog post.
Azure Ultra Disk Storage was first introduced as a preview in September 2018, initially limited to the East US 2 region. With general availability, Microsoft has expanded access to the service and is making it commercially supported for production workloads.
Key Performance Specifications
Azure Ultra Disk Storage gives customers fine-grained control over their storage performance profile. Configurable parameters include:
- Disk size: 4 GiB up to 64 TiB
- Throughput (bandwidth): 300 MB/s up to 2,000 MB/s
- IOPS: 1,200 IOPS up to 160,000 IOPS
These parameters can be adjusted independently, allowing teams to right-size storage performance relative to their actual workload demands without over-provisioning capacity.
Dynamic Performance Tuning Without Downtime
One of the most operationally significant features of Ultra Disk Storage is the ability to modify throughput and IOPS settings without detaching the disk or restarting the virtual machine. Mark Russinovich, Chief Technology Officer for Azure, highlighted this capability in the launch announcement:
One key benefit of Ultra Disk Storage is that you can dynamically tune disk performance without detaching your disk or restarting your virtual machines. Thus, you can scale performance along with your workload. When you adjust either IOPS or throughput, the new performance settings take effect in less than an hour.
— Mark Russinovich, CTO, Microsoft Azure
This live-adjustment capability is particularly valuable for workloads with variable I/O patterns, enabling cost-effective performance scaling without service interruptions.
How Ultra Disk Storage Differs from Other Azure Disk Types
With Ultra Disk Storage, Microsoft now offers four tiers of persistent managed disk storage:
- Ultra Disk Storage – Highest performance SSD tier, sub-millisecond latency, for mission-critical I/O-intensive workloads
- Premium SSD – High-performance SSD backed by Azure Blob storage cache, suitable for production workloads
- Standard SSD – Consistent SSD performance for web servers and lightly loaded applications
- Standard HDD – Cost-effective spinning disk storage for backup, archival, and infrequently accessed data
A key architectural difference between Ultra Disks and Premium SSDs is the redundancy and data path model. Premium SSD relies on the Azure Blob storage cache layer. Ultra Disks use Locally Redundant Storage (LRS), maintaining three copies of data within a single Azure Availability Zone.
Additionally, Ultra Disks use Microsoft’s virtual disk client technology. This provides metadata on disk mappings and allows client VMs to communicate directly with storage servers, bypassing the load balancers and front-end servers used for initial disk connections. The result is lower latency and more predictable I/O performance.
Target Workloads and Enterprise Use Cases
Azure Ultra Disk Storage is designed for data-intensive, latency-sensitive workloads that were historically difficult to run in the cloud with acceptable performance. Typical use cases include:
- SAP HANA and other in-memory databases
- High-performance relational databases (SQL Server, Oracle, MySQL at scale)
- NoSQL databases requiring consistent low-latency I/O
- Mission-critical enterprise application lift-and-shift migrations
- High-throughput analytics and data processing pipelines
Charles King, principal analyst at Pund-IT, commented on the enterprise significance of the launch in a DataCenterKnowledge article:
Azure Ultra Disk Storage’s high throughput and high I/O capabilities were designed for supporting data-intensive workloads like SAP HANA in the cloud. That should make the new service particularly interesting to Microsoft’s enterprise clients and could also increase the momentum of mission-critical application migrations to Microsoft Azure.
— Charles King, Principal Analyst, Pund-IT
Regional Availability and Pricing
At the time of general availability announcement, Azure Ultra Disk Storage was available in three Azure regions:
- East US 2
- North Europe
- Southeast Asia
General availability pricing was set to take effect from 1 October 2019. Customers evaluating the service should consult the official Azure Managed Disks pricing page for current rates and region availability, as both may have expanded since this announcement.
Ultra Disks require VMs that support the Ultra Disk Storage tier — not all Azure VM sizes or series are compatible. Verify VM compatibility in the Azure documentation before planning a migration.