That physical unused space is the hot spare.
See output for pools, volume, disk groups and disks:
# show pools
Name Serial Number Blocksize Total Size Avail Snap Size OverCommit Disk Groups Volumes Low Thresh
Mid Thresh High Thresh Sec Fmt Health Reason Action
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A xxx 512 6698.0GiB 2254.3GiB 0iB Enabled 2 1 50.00 %
75.00 % 97.01 % 512e OK
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# show volumes
Pool Name Total Size Alloc Size Type Health Reason Action
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A MSA2050-SAS 6698.0GiB 4443.7GiB base OK
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# show disk-groups
Name Blocksize Size Free Pool Tier % of Pool Own Pref RAID Disks Spr Chk Status Jobs
Job% Serial Number Spin Down SD Delay Sec Fmt Health Reason
Action
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SAS-dgA01 512 6698.0GiB 2254.3GiB A Standard 100 A A RAID5 5 0 512k FTOL VRSC
36% xxx Disabled 0 512e OK
rcA1 512 1486.9GiB 0iB A Read Cache 0 A A NRAID 1 0 N/A UP
xxx Disabled 0 512e OK
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# show disks
Location Serial Number Vendor Rev Description Usage Jobs Speed (kr/min) Size Sec Fmt
Disk Group Pool Tier Health
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1.1 xxx HP HPD6 SSD SAS VIRTUAL POOL 0 1490.4GiB 512e
rcA1 A Read Cache OK
1.2 xxxHP HPD6 SSD SAS AVAIL 0 1490.4GiB 512e
N/A OK
1.9 xxxHP HPD2 SAS VIRTUAL POOL VRSC 10 1676.7GiB 512e
SAS-dgA01 A Standard OK
1.10 xxxHP HPD2 SAS VIRTUAL POOL VRSC 10 1676.7GiB 512e
SAS-dgA01 A Standard OK
1.11 xxHP HPD2 SAS VIRTUAL POOL VRSC 10 1676.7GiB 512e
SAS-dgA01 A Standard OK
1.12 xxxHP HPD2 SAS VIRTUAL POOL VRSC 10 1676.7GiB 512e
SAS-dgA01 A Standard OK
1.13 xxxHP HPD2 SAS VIRTUAL POOL VRSC 10 1676.7GiB 512e
SAS-dgA01 A Standard OK
1.23 xxxHP HPD2 SAS GLOBAL SP 10 1676.7GiB 512e
N/A OK
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