eG Help

A parity group is a group of hard disk drives (HDDs) that form the basic unit of storage for the TagmaStore USP and NSC subsystem. All HDDs in a parity group must have the same physical capacity.

If the monitor data shows overall high parity group usage, you should consider installing additional HDDs and using Volume Migration migrate the high-usage volumes to the new parity groups. If the monitor data shows the imbalance usage of the parity group, you can use Volume Migration to migrate volumes from high-usage parity groups to low-usage parity groups.

This test is used to identify the overall health of the Parity Group. Parity group usage should be balanced across all parity groups.

Measurement	Description	Measurement Unit
IOPS	This measure indicates the number of read/write operations of the Parity Group made per second.	IOPS
TransRate	This measure indicates the size of data of the Parity Group that has been transferred per second.	KB/sec
Read_IOPS	This measure indicates the number of read operations of the Parity Group made per second.	IOPS
Write_IOPS	This measure indicates the number of write operations of the Parity Group made per second.	IOPS
Read_Hit	This measure indicates the read hit ratio of the Parity Group in percent.	%
Write_Hit	This measure indicates the write hit ratio of the Parity Group in percent.	%
C2D_Transfer	This measure indicates the number of data like parity groups, external volume groups, or V-VOL groups of the Parity Group that has been transferred per second between cache memories and disk drives.	Number
Response_Time	This measure indicates the response time of the Parity Group, external volume groups, or V-VOL groups in microseconds.	Microseconds
Backtrans	This measure indicates data of the Parity Group that has been transferred between cache memories and disk drives.	Number