Space reclamation on FlexVol

[not_a_Lone_wolf]

Hello Team.

Vol A was 15TB, and later decreased to 10 TB due to less utilization. However, the logical used size as reported in vol show output is still the older one, and Logical Used Percentage: 144%. The volume has the following attributes set : Space SLO: none and Space Guarantee Style: volume. I know that when Space Guarantee Style is set to volume, ONTAP reserves certain set of blocks for that volume in the underlying aggregate. Now, the issue is, if I leave the volume as it is, would it be an issue in terms of space issues later on that cluster (since those blocks would still be reserved for this volume) ? I tried to run compaction but that won't work since the Space Guarantee Style is volume. I would really be grateful if somebody could share their expert insights. 

Please note: Vol has static data and is on Prod cluster.

[AlexDawson]

Hi there! Can you check what snapshots are present in the volume?

[not_a_Lone_wolf]

Hi @AlexDawson 

Thanks for the reply.

There's only one baseline snapshot of 592KB(this is a source volume). I have updated the notes with the vol show -instance output. (few details have been replaced with XXXX for privacy)

Vserver Name: XXXXXX
Volume Name: XXXXXX
Aggregate Name: XXXXXX
List of Aggregates for FlexGroup Constituents: XXXXXX
List of Nodes Hosting the Volume: XXXXXX
Volume Size: 10TB
Volume Data Set ID: 1083
Volume Master Data Set ID: 2162040987
Volume State: online
Volume Style: flex
Extended Volume Style: flexvol
FlexCache Endpoint Type: none
Is Cluster-Mode Volume: true
Is Constituent Volume: false
Export Policy: XXXXXX
User ID: 0
Group ID: 0
Security Style: unix
UNIX Permissions: ---rwxr-xr-x
Junction Path: XXXXXX
Junction Path Source: RW_volume
Junction Active: true
Junction Parent Volume: XXXXXX
Comment:
Available Size: 1.90TB
Filesystem Size: 10TB
Total User-Visible Size: 9.50TB
Used Size: 7.60TB
Used Percentage: 80%
Volume Nearly Full Threshold Percent: 95%
Volume Full Threshold Percent: 98%
Maximum Autosize: 16.80TB
Minimum Autosize: 10TB
Autosize Grow Threshold Percentage: 98%
Autosize Shrink Threshold Percentage: 50%
Autosize Mode: off
Total Files (for user-visible data): 21251126
Files Used (for user-visible data): 127630
Space Guarantee in Effect: true
Space SLO in Effect: true
Space SLO: none
Space Guarantee Style: volume
Fractional Reserve: 100%
Volume Type: RW
Snapshot Directory Access Enabled: true
Space Reserved for Snapshot Copies: 5%
Snapshot Reserve Used: 0%
Snapshot Policy: none
Creation Time: Tue Mar 24 10:14:10 2020
Language: C.UTF-8
Clone Volume: false
Node name: XXXXX
Clone Parent Vserver Name: -
FlexClone Parent Volume: -
NVFAIL Option: off
Volume's NVFAIL State: false
Force NVFAIL on MetroCluster Switchover: off
Is File System Size Fixed: false
(DEPRECATED)-Extent Option: off
Reserved Space for Overwrites: 0B
Primary Space Management Strategy: volume_grow
Read Reallocation Option: off
Naming Scheme for Automatic Snapshot Copies: create_time
Inconsistency in the File System: false
Is Volume Quiesced (On-Disk): false
Is Volume Quiesced (In-Memory): false
Volume Contains Shared or Compressed Data: true
Space Saved by Storage Efficiency: 6.08TB
Percentage Saved by Storage Efficiency: 44%
Space Saved by Deduplication: 6.08TB
Percentage Saved by Deduplication: 44%
Space Shared by Deduplication: 435.1GB
Space Saved by Compression: 0B
Percentage Space Saved by Compression: 0%
Volume Size Used by Snapshot Copies: 592KB
Block Type: 64-bit
Is Volume Moving: false
Flash Pool Caching Eligibility: read-write
Flash Pool Write Caching Ineligibility Reason: -
Constituent Volume Role: -
QoS Policy Group Name: -
QoS Adaptive Policy Group Name: -
Caching Policy Name: -
Is Volume Move in Cutover Phase: false
Number of Snapshot Copies in the Volume: 1
VBN_BAD may be present in the active filesystem: false
Is Volume on a hybrid aggregate: false
Total Physical Used Size: 7.60TB
Physical Used Percentage: 76%
Is Volume a FlexGroup: false
SnapLock Type: non-snaplock
Vserver DR Protection: -
Enable Encryption: false
Is Volume Encrypted: false
Volume Encryption State: none
Encryption Key ID:
Application: -
Is Fenced for Protocol Access: false
Protocol Access Fence Owner: -
Is SIDL enabled: off
Over Provisioned Size: 0B
Available Snapshot Reserve Size: 512.0GB
Logical Used Size: 13.68TB
Logical Used Percentage: 144%
Logical Available Size: -
Logical Size Used by Active Filesystem: 13.68TB
Logical Size Used by All Snapshots: 6.08TB
Logical Space Reporting: false
Logical Space Enforcement: false
Volume Tiering Policy: none
Performance Tier Inactive User Data: -
Performance Tier Inactive User Data Percent: -

[not_a_Lone_wolf]

Hi @AlexDawson ,

Thanks for the reply.

This volume has only a baseline snapshot (Source volume). I am sharing the output of vol show -instance below:

Volume Size: 10TB
Volume Data Set ID: 1083
Volume Master Data Set ID: 2162040987
Volume State: online
Volume Style: flex
Extended Volume Style: flexvol
FlexCache Endpoint Type: none
Is Cluster-Mode Volume: true
Is Constituent Volume: false
Export Policy: XXXX
User ID: 0
Group ID: 0
Security Style: unix
UNIX Permissions: ---rwxr-xr-x
Junction Path: /XXXX
Junction Path Source: RW_volume
Junction Active: true
Junction Parent Volume: XXXX_root
Comment:
Available Size: 1.90TB
Filesystem Size: 10TB
Total User-Visible Size: 9.50TB
Used Size: 7.60TB
Used Percentage: 80%
Volume Nearly Full Threshold Percent: 95%
Volume Full Threshold Percent: 98%
Maximum Autosize: 16.80TB
Minimum Autosize: 10TB
Autosize Grow Threshold Percentage: 98%
Autosize Shrink Threshold Percentage: 50%
Autosize Mode: off
Total Files (for user-visible data): 21251126
Files Used (for user-visible data): 127630
Space Guarantee in Effect: true
Space SLO in Effect: true
Space SLO: none
Space Guarantee Style: volume
Fractional Reserve: 100%
Volume Type: RW
Snapshot Directory Access Enabled: true
Space Reserved for Snapshot Copies: 5%
Snapshot Reserve Used: 0%
Snapshot Policy: none
Creation Time: Tue Mar 24 10:14:10 2020
Language: C.UTF-8
Clone Volume: false
Node name: XXXX
Clone Parent Vserver Name: -
FlexClone Parent Volume: -
NVFAIL Option: off
Volume's NVFAIL State: false
Force NVFAIL on MetroCluster Switchover: off
Is File System Size Fixed: false
(DEPRECATED)-Extent Option: off
Reserved Space for Overwrites: 0B
Primary Space Management Strategy: volume_grow
Read Reallocation Option: off
Naming Scheme for Automatic Snapshot Copies: create_time
Inconsistency in the File System: false
Is Volume Quiesced (On-Disk): false
Is Volume Quiesced (In-Memory): false
Volume Contains Shared or Compressed Data: true
Space Saved by Storage Efficiency: 6.08TB
Percentage Saved by Storage Efficiency: 44%
Space Saved by Deduplication: 6.08TB
Percentage Saved by Deduplication: 44%
Space Shared by Deduplication: 435.1GB
Space Saved by Compression: 0B
Percentage Space Saved by Compression: 0%
Volume Size Used by Snapshot Copies: 91.50MB
Block Type: 64-bit
Is Volume Moving: false
Flash Pool Caching Eligibility: read-write
Flash Pool Write Caching Ineligibility Reason: -
Constituent Volume Role: -
QoS Policy Group Name: -
QoS Adaptive Policy Group Name: -
Caching Policy Name: -
Is Volume Move in Cutover Phase: false
Number of Snapshot Copies in the Volume: 1
VBN_BAD may be present in the active filesystem: false
Is Volume on a hybrid aggregate: false
Total Physical Used Size: 7.60TB
Physical Used Percentage: 76%
Is Volume a FlexGroup: false
SnapLock Type: non-snaplock
Vserver DR Protection: -
Enable Encryption: false
Is Volume Encrypted: false
Volume Encryption State: none
Encryption Key ID:
Application: -
Is Fenced for Protocol Access: false
Protocol Access Fence Owner: -
Is SIDL enabled: off
Over Provisioned Size: 0B
Available Snapshot Reserve Size: 511.9GB
Logical Used Size: 13.68TB
Logical Used Percentage: 144%
Logical Available Size: -
Logical Size Used by Active Filesystem: 13.68TB
Logical Size Used by All Snapshots: 6.08TB
Logical Space Reporting: false
Logical Space Enforcement: false
Volume Tiering Policy: none
Performance Tier Inactive User Data: -
Performance Tier Inactive User Data Percent: -