Using non-volatile memory (NVDIMM-N) as block storage in Windows Server 2016 Tobias Klima Program Manager

Use Case Example – Fast Transactions in SQL Server Problem DB Transactions gated by log commit speed The faster the log, the more DB updates possible Opportunity Accelerate Log Commits Accelerate DB Provide better customer SLAs Approach Log on SCM – Persistent Medium on Memory Bus NVDIMM-N supported in WS 2016 NVDIMM-N based on DDR4 RAM + Flash for backup Exposes Block Interface (like a Disk) SCM Traditional Storage PCIe CPU SATA SAS NVDIMM-N NVMe AHCI HBA Memory

Technology Evolution & Old Assumptions Microsoft Build 2016 6/22/2018 8:59 PM Technology Evolution & Old Assumptions Storage technology has made significant strides (capacity, latency, throughput). Capacity: Large Latency: High Throughput: Low HDD (SATA/SAS) Capacity: Medium Latency: Medium Throughput: Medium SSD (SATA/SAS) SCM Performance breaks assumptions about “slow storage” in today’s software For the highest performance, use byte- addressability (app changes) For early adoption and easy use, utilize it as a block device (no app changes) Capacity: Medium Latency: Low Throughput: High PCIe SSD (AHCI/NVMe) Capacity: Small Latency: Very Low Throughput: Very High NVDIMM-N (SCM) © 2016 Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

Block Mode Architecture (In Software) Standard Raw Disk Access Standard File API The Idea Block Interface on top of the memory ranges of SCM device Facts Compatible with existing applications (ReadFile, WriteFile) Extremely fast “disk” – <10us for 4k I/O Disk Filter Drivers may not work (e.g. Disk Accelerometer, low-level “accelerators”) Application Application User Mode Kernel Mode File System SCM Bus Driver SCM Disk Driver Enumerates SCM Device Load/Store Operations SCM

NVDIMM-N Block Mode Performance Tobias Klima Hardware Provided By:

Device Management Like a Disk Exposed in OS as a new disk device Microsoft Build 2016 6/22/2018 8:59 PM Device Management Like a Disk Exposed in OS as a new disk device Re-uses existing PowerShell cmdlets: Get-PhysicalDisk Get-StorageReliabilityCounter Enabled by Microsoft-defined _DSM specification (MSDN) Useable in Storage Spaces for striping, mirroring, write-back caching © 2016 Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

Call to Action How would you change your app, if you could do fast, reliable, synchronous I/O? What data (structures) do your apps use frequently? Which need the lowest possible access latencies? Re-visit Build on Channel 9. Continue your education at Microsoft Virtual Academy online.

6/22/2018 8:59 PM © 2016 Microsoft Corporation. All rights reserved. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.