HP StorageWorks Storage Mirroring for Linux Scripting Guide (T2558-96319, June 2009)

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StatsPort Port used by DTStat to gather Storage Mirroring statistics
Values:
1025 - 65535
Default: 1106
GUI Setting: None
If you change this value, the source service must be stopped and restarted to
implement the change.
StatsShmSize This entry is no longer used.
StatsWriteInterval
Interval, in minutes, in which statistics are written to the
statistic.sts
file
Values: 0 - 65535
Default: 5
GUI Setting: Server Properties, Logging tab, Statistics, Write Interval
SystemMemory
Limit
Set by the Storage Mirroring service, each time it is started, to record the
amount of available memory.
TargetPaused Internal setting that indicates if the target machine is paused. Do not modify
this setting.
TargetPaused
Virtual
Internal setting that indicates which target machines are paused. Do not
modify this setting.
TCPBufferSize Size of the TCP/IP buffer in bytes.
Values:
4096-7500000
Default: 375000
GUI Setting: None
The default setting creates a TCP window that will accommodate most
environments. In most environments, this value will not need to be adjusted.
However, if your Storage Mirroring network has a long end-to-end route and
the throughput is not where you would expect it to be, then adjusting this
parameter may have beneficial results. This value is the bandwidth delay
product, which is calculated using the bandwidth of the network (in
bits/second) times the round trip time (in seconds) between the two ends.
Some recommended settings to improve Storage Mirroring throughput
performance are:
Gigabit LAN—The setting should be changed to 375000.
WAN—The setting should be adjusted to 130000.
While the calculations are fairly straight forward, the values that have been
suggested are not exact because they depend on round trip time. Some
improvements could be gained by adjusting these values either higher or
lower. The value suited for your environment can best be determined through
trial and error testing.
TGCloseDelay The length of time, in milliseconds, a file is held open on the target
Values: 0 - 2000
Default: 1000
GUI Setting: None
If disk caching on the target is disabled either manually or by default (for
example, by default on disks that host Active Directory database files), the
target system may be slow during a mirror. If so, descreasing this setting to
100, 10, and 0 will result in incremental improvements, with 0 returning the
system performance to normal.
Server Setting Description