Automatic Space Sharing of Disaggregated Storage of a Storage Pod by Multiple Nodes of a Distributed Storage System

Patent metadata

Field	Value
Publication number	US-2025284417-A1
Application number	US-202418595785-A
Country	US
Kind code	A1
Filing date	Mar 5, 2024
Priority date	Mar 5, 2024
Publication date	Sep 11, 2025
Grant date	—

Abstract

Systems and methods are provided for implementation and use of disaggregated storage by a distributed storage system. In various examples described herein, the association of blocks of storage space within a storage pod with a given dynamically extensible file system (DEFS) may be in large chunks of one or more gigabytes (GB), which may be referred to herein as “allocation areas” (AAs) that each include multiple RAID stripes. The use of large, multi-GB chunks, as the unit of space allocation/assignment to DEFSs of a distributed storage system facilitates ease of management and independence of write allocation. The use of AAs described herein further allows disk space to be used more fluidly across individual (nodes) storage systems of a distributed storage system (cluster of nodes working together), thereby eliminating silos of storage; and processing resource (e.g., CPU) load may be distributed across the cluster.

First claim

What is claimed is:

1 . A method comprising:
providing a storage pod having a group of disks containing multiple Redundant Array of Independent Disks (RAID) groups, wherein the storage pod is accessible concurrently to all nodes of a plurality of nodes of a cluster representing a distributed storage system via a global physical volume block number (PVBN) space; monitoring, by a node of the cluster, storage space availability or usage by one or more dynamically extensible file systems (DEFSs) of the node; based on the storage space availability or usage meeting a predetermined or configurable threshold in relation to storage space availability or usage of one or more DEFSs of one or more other nodes of the plurality of nodes of the cluster, requesting ownership of one or more allocation areas (AA) within the global PVBN space currently owned by the one or more DEFSs of the one or more other nodes be transferred to the node.

2 . The method of claim 1 , wherein said requesting ownership includes sending a space request message from the node on behalf of a donee DEFS of the one or more DEFSs of the node to a donor DEFS of the one or more DEFSs of a second node of the one or more other nodes.

3 . The method of claim 2 , wherein the space request message is sent via an on-wire internode communication mechanism to the second node.

4 . The method of claim 2 , wherein the space request message is posted to a persistent message queue of the donor DEFS or the second node.

5 . The method of claim 1 , further comprising after receiving the space request message, selecting, by the donor DEFS, an AA to donate to the donee DEFS from among a plurality of AAs owned by the donee DEFS by prioritizing free AAs over partial AAs.

6 . The method of claim 5 , further comprising sending an AA ownership change message from the second node to the first node, wherein the AA ownership change message includes an AA identifier of the selected AA.

7 . A method comprising:
providing a storage pod having a group of disks containing multiple Redundant Array of Independent Disks (RAID) groups, wherein the storage pod is accessible concurrently to all nodes of a plurality of nodes of a cluster representing a distributed storage system via a global physical volume block number (PVBN) space; tracking, by each node of the cluster, a space metric indicative of storage space availability or usage by a first set of one or more DEFSs of the node; and notifying, by each node of the cluster, one or more other nodes of the plurality of nodes of the cluster regarding the space metric of the node.

8 . The method of claim 7 , wherein the global PVBN space is partitioned into a plurality of allocation areas (AAs) and wherein the method further comprises based on the tracking and the notifying, performing space balancing among the first set of one or more DEFSs and a second set of one or more DEFSs of a second node of the plurality of nodes of the cluster by changing ownership of one or more of the plurality of AAs owned by a first DEFS of the first set of one or more DEFSs to a second DEFS of the second set of one or more DEFSs.

9 . The method of claim 7 , further comprising determining a cluster-wide space metric based at least in part on space metrics received from all other nodes of the cluster.

10 . The method of claim 9 , further comprising determining an average node space metric by dividing the cluster-wide space metric by a number of the plurality of nodes.

11 . The method of claim 10 , further comprising based on the space metric meeting a predetermined or configurable threshold in relation to the average node space metric, requesting storage space from one or more DEFSs of the one or more other nodes.

12 . The method of claim 7 , wherein said notifying comprises responding to a polling request for the space metric received from the one or more other nodes.

13 . The method of claim 7 , wherein said notifying comprises sending a space reporting message, including the space metric, to each of the one or more other node.

14 . A non-transitory machine readable medium storing instructions, which when executed by one or more processing resources of a distributed storage system, cause the distributed storage system to:
provide a storage pod having a group of disks containing multiple Redundant Array of Independent Disks (RAID) groups, wherein the storage pod is accessible concurrently to all nodes of a plurality of nodes of a cluster representing a distributed storage system via a global physical volume block number (PVBN) space; monitor storage space availability or usage by one or more dynamically extensible file systems (DEFSs) of a node of the plurality of nodes; based on the storage space availability or usage meeting a predetermined or configurable threshold in relation to storage space availability or usage of one or more DEFSs of one or more other nodes of the plurality of nodes of the cluster, request ownership of one or more allocation areas (AA) within the global PVBN space currently owned by the one or more DEFSs of the one or more other nodes be transferred to the node.

15 . The non-transitory machine readable medium of claim 14 , wherein requesting transfer of ownership includes sending a space request message from the node on behalf of a donee DEFS of the one or more DEFSs of the node to a donor DEFS of the one or more DEFSs of a second node of the one or more other nodes.

16 . The non-transitory machine readable medium of claim 15 , wherein the space request message is sent via an on-wire internode communication mechanism to the second node.

17 . The non-transitory machine readable medium of claim 15 , wherein the space request message is posted to a persistent message queue of the donor DEFS or the second node.

18 . The non-transitory machine readable medium of claim 14 , wherein the instructions further cause the distributed storage system to, after receipt of the space request message, select, by the donor DEFS, an AA to donate to the donee DEFS from among a plurality of AAs owned by the donee DEFS by prioritizing free AAs over partial AAs.

19 . The non-transitory machine readable medium of claim 18 , wherein the instructions further cause the distributed storage system to send an AA ownership change message from the second node to the first node, wherein the AA ownership change message includes an AA identifier of the selected AA.

20 . A distributed storage system comprising:
one or more processing resources; and instructions that when executed by the one or more processing resources cause the distributed storage system to:
provide a storage pod having a group of disks containing multiple Redundant Array of Independent Disks (RAID) groups, wherein the storage pod is accessible concurrently to all nodes of a plurality of nodes of a cluster representing a distributed storage system via a global physical volume block number (PVBN) space;
monitor storage space availability or usage by one or more dynamically extensible file systems (DEFSs) of a node of the plurality of nodes;
based on the storage space availability or usage meeting a predetermined or configurable threshold in relation to storage space availability or usage of one or more DEFSs of one or more other nodes of the plurality of nodes of the cluster, request ownership of one or more allocation areas (AA) within the global PVBN space currently owned by the one or more DEFSs of the one or more other nodes be transferred to the node.

Assignees

• Netapp Inc

Inventors

• Thoppil Anil Paul
• Subramanian Ananthan
• Urkude Suhas
• Banerjee Arindam
• Jernigan Iv Richard Parvin

Classifications

• G06F3/061

  Improving I/O performance · CPC title

• G06F3/067

  Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS] · CPC title

• G06F3/0604

  Improving or facilitating administration, e.g. storage management · CPC title

• G06F3/0689

  Disk arrays, e.g. RAID, JBOD · CPC title

• G06F3/0631 Primary

  by allocating resources to storage systems · CPC title