With SQL Server 2019, how do you configure PMEM on an Azure VM?

Hi @Hulings, David,

Thanks for reaching out to Microsoft QA.

It seems you're aiming to set up Persistent Memory (PMEM) for SQL Server 2019 on an Azure Virtual Machine and have questions regarding Intel Optane NVRAM requirements and which VM configurations support it. To begin using Persistent Memory (PMEM) with SQL Server 2019 on Azure Virtual Machines, follow these key steps:

1. Prerequisites: -Ensure your Azure VM is running Windows Server 2019 or later, as this is required to use the ipmctl utility for configuring PMEM devices.
2. Compatible Azure VM Types: - Not all Azure VM types support persistent memory. You’ll need to use VM instances that offer NVDIMM support or are equipped with Intel Optane technology. These are typically specialized or high-performance configurations.

Azure Virtual Machine (VM) sizes that support Persistent Memory (PMem) are primarily found in the ** M-series**, Msv2-series, Mdsv2-series, and Ebsv5/Ebdsv5-series families, which are designed for memory-optimized workloads.

1. Configuring Persistent Memory (PMEM) for SQL Server 2019 on Azure: -

·          Use the ipmctl command-line utility to initialize and manage PMEM devices.

·         Create namespaces for the persistent memory devices to enable SQL Server to access them.

·         For optimal performance, configure SQL Server databases to use PMEM in DAX (Direct Access) mode. This allows direct memory-mapped access, bypassing the file system cache.

Important: Do not place transaction log files on PMEM unless sector atomicity is guaranteed—typically achieved using Block Translation Table (BTT) mode.

1. Intel Optane and Hardware Requirements: -

While Intel Optane is not strictly required, it is the most used hardware for enabling PMEM due to its high performance and persistence characteristics.

Azure VMs must be provisioned with NVDIMM-compatible hardware or Intel Optane PMem modules to support persistent memory.

Not all Azure VM types support PMEM. You should consult the https://free.blessedness.top/en-us/sql/database-engine/configure-windows/configure-persistent-memory?view=sql-server-ver17 for a list of supported VM sizes and configurations.

1. Resources: You can find detailed instructions on configuring PMEM in the links provided in the Microsoft documentation:

Configure Persistent Memory for SQL Server on Windows

https://free.blessedness.top/en-us/azure/virtual-machines/sizes/memory-optimized/m-family?tabs=mbsv3%2Cmsv3mm%2Cmsv3hm%2Cmsv2mm

Regards,
Vrishabh