Mode
Description
689
Allows you to suppress initial copy operations when the write-pending level
to the MP blade of the S-VOL is 60% or higher.
•
ON: The initial copy is suppressed.
•
OFF (default): The initial copy is not suppressed.
784
Allows you to reduce RIO MIH time to five seconds. As a result, after a
remote path error, less time elapses until the operation is retried on an
alternate path. (Both RIO MIH time and the Abort Sequence timeout value
are combined for this retry time.)
•
ON: Reduces the RIO MIH time to five seconds.
Combined with the Abort Sequence timeout value, the total amount of
time that elapses before the operation is retried on another path is a
maximum of 10 seconds.
•
OFF (default): The RIO MIH time that you specified when the secondary
system was registered is used with the specified Abort Sequence
timeout value. The default is 15 seconds.
If the RIO timeout time and the ABTS timeout time elapse, an attempt is
made to retry RIO in the alternate path.
Planning system performance
Remote copy operations can affect the I/O performance of host servers and
the primary and secondary storage systems. You can minimize the effects of
remote copy operations and maximize efficiency and speed by changing your
remote connection options and remote replica options.
Hitachi Data Systems customer support can help you analyze your workload
and optimize copy operations. Using workload data (MB/s and IOPS), you can
determine the appropriate amount of bandwidth, number of physical paths,
and number of ports for your global-active device system. When these are
properly determined and sized, the data path operates free of bottlenecks
under all workload levels.
Related topics
•
Hitachi Dynamic Link Manager on page 3-3
Hitachi Dynamic Link Manager
Hitachi Dynamic Link Manager (HDLM) allows you to specify alternate paths
to be used for normal global-active device operations. Other paths are used
when failures occur in the paths (including alternate paths) that should be
used for normal operations. Host mode option 78, the nonpreferred path
option, must be configured to specify nonpreferred paths, which are used
when failures occur.
For example, if servers and storage systems are connected in a cross-path
configuration, I/O response is prolonged because the primary-site server is
distant from the secondary system, and the secondary-site server is distant
Planning for global-active device
3-3
Hitachi Virtual Storage Platform G1000 Global-Active Device User Guide
Summary of Contents for G1000
Page 8: ...Index viii Hitachi Virtual Storage Platform G1000 Global Active Device User Guide ...
Page 14: ...xiv Preface Hitachi Virtual Storage Platform G1000 Global Active Device User Guide ...
Page 238: ...9 18 Troubleshooting Hitachi Virtual Storage Platform G1000 Global Active Device User Guide ...
Page 245: ...Hitachi Virtual Storage Platform G1000 Global Active Device User Guide ...