Release Notes

Fixed Issues Related to Data Reduction
The following issues are fixed in Storage Center 7.4:
Table 8. Fixed Data Reduction Issues in Storage Center 7.4.20
Issue Description
SCOS-60622 Deduplication might pause because Storage Center keeps changing the Dedup capable
attribute to False for pagepools that support deduplication.
SCOS-60386 A storage system might fail to completely defragment partial pages because of a change
introduced in Storage Center 7.4.5.
SCOS-60224 Optimized data might become unavailable if data optimization memory is maxed out due to a
memory leak.
SCOS-58788 Page statistics for the active snapshot might be incorrect after data progression.
SCOS-54606 On storage systems that use compression, data progression might fail with an out of memory
error.
Table 9. Fixed Data Reduction Issues in Storage Center 7.4.2
Issue Description
SCOS-55306 Data progression might become suspended and fail to resume if DPM defragment and data
progression are running simultaneously.
SCOS-54988 Secondary storage data might be erroneously recovered as lost space during data progression.
SCOS-54249 On a storage system running deduplication, the deduplication ratio might be low because of an
issue that prevents the deduplication dictionary from growing.
SCOS-54180 On a storage system with volumes that have many optimized pages, a controller might reset
because of a memory exhaustion issue.
SCOS-54104 Deduplication might fail to occur on a storage system because the Data Optimization
Deduplication Capable attributes are set to false after a storage system is updated to Storage
Center 7.3.4 or later.
SCOS-54101 A RAID restripe might not be able to make progress if there are too many DPM/PPM lost
partial pages.
SCOS-52707 An SC8000 controller with 16 GB of memory might reset if the deduplication dictionary grows
too large.
SCOS-49144 Data progression might stop running or the Storage Center might reset when a payload
checksum failure occurs due to table entries being read incorrectly from memory.
SCOS-49069 In rare instances, increased latency might occur on a storage system if a pagepool
consolidation process is active.
SCOS-48236 A restripe statistic might be incorrect within a 5-minute window during which a copy
completes.
Fixed Issues Related to Hardware
The following issues are fixed in Storage Center 7.4:
Table 10. Fixed Hardware Issues in Storage Center 7.4.20
Issue Description
SCOS-59595 On Chelsio T5 or T6 iSCSI HBAs, the target connection code might prevent the SACK-
permitted option from being set in response to a connection request from a SCSI initiator,
which could impact read I/O performance.
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