SNIA-SDC23-Holmberg-Maisenbacher-Zones-Art-Log-Structured-Storage.pdf

1、1|2023 Western Digital Corporation.All Rights Reserved.Virtual ConferenceSeptember 28-29,2021Zones and The Art of Log Structured StorageHans Holmberg and Dennis Maisenbacher2|2023 Western Digital Corporation.All Rights Reserved.What is Zoned Storage?A media independent storage interfaceInherits the

2、existing concepts of logical blocks,LBAs,I/O Commands(e.g.,Read and Write commands),Logical blocks are divided into fixed-sized zones,which are then utilized for data placement by the host softwareSame interface for flash and HDDsBoth conventional and zoned interfaces can be exposed by the same driv

3、eE.g.,useful for soft roll-outs as software is updated to take advantage of the zoned storage modelNVMe Namespace(NVM Command Set)LBA012X-1Zoned Namespace(NVM and the Zoned Namespace Command Set)LBA012X-1ZoneZone 0Zone YZone 1Write pointerpositionWrite operationsadvance the write pointerA Zone Reset

4、rewinds the write pointerThe NVMe and NVMe-oF word marks are trademarks of NVM Express,Inc.3|2023 Western Digital Corporation.All Rights Reserved.HDDsSMR HDDs offer 18%additional capacity with the newest 26TB SMR HDD over conventional CMR HDDFlashSSDs with Zoned Namespace support offer 3-4x higher p

5、erformance,predictable latency,7-28%higher capacityWhy Zoned Storage?WriteAmplificationImage sources:zonedstorage.io 4|2023 Western Digital Corporation.All Rights Reserved.Zoned Storage vs Modern Workloads Modern storage workloads rely heavily on out-of-place sequential writes Aligns with media char

6、acteristics Provide higher throughput Aids recovery Enables easy snapshotting A great fit for zoned storage!Examples Log structured merge tree data Copy on write file systems 5|2023 Western Digital Corporation.All Rights Reserved.Zoned Storage Evolution Broad industry need for a standardized approac