Storage Mirroring User Guide

14 - 24
StatsWriteInterval Interval, in minutes, in which statistics are written to the statistic.sts file
Values: 0 - 65535
Default: 5
SystemMemoryLimit 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.
TargetPausedVirtual 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:
37500
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.
Te m p D i r Temporary directory used when replicating Windows 200x encrypted files.
TGCloseDelay The length of time, in milliseconds, a file is help open on the target
Values: 0 - 2000
Default: 1000
TGDisableAttribute
Replication
Specifies whether or not the attributes compression, ACL, and file mask are written to the
target during mirroring and replication
Values: (0) Enable attribute replication
(
1) Disable attribute replication
Default: 0
TGExecutionRetry
Limit
The number of times an unfinished operation will be retried on the target before it is discarded. If
this value is set to zero (
0), an operation will never be discarded and will be retried on the target
until it is applied.
Values: 0 - 65536
Default: 0
TGFileAlloc Indicates that Storage Mirroring allocates an entire file on the first write of a mirror operation
Values: (0) Disabled
(
1) Enabled
Default: 1
To help eliminate file fragmentation on the target server, Storage Mirroring should allocate the
entire file first. With extremely large files, the file allocation may take a long time. Therefore, you
may want to disable the file allocation. If you disable file allocation, you will have more
fragmentation on the target disk.
TGMirrorCapacity
High
Maximum percentage of system memory that can contain mirror data before the target signals
the source to pause the sending of mirror operations.
Values: 2-75
Default: 20
Program Setting Description