The subkey for the Rdr (redirector) service has the following Registry path:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Rdr\Parameters
For the search buffer sizes defined in the following entries: If the buffer passed for the search is less than the LowerSearchThreshold value, the system requests LowerSearchThreshold bytes of data from the server. If the buffer size is between the value of LowerSearchThreshold and UpperSearchBufferSize, the system uses the buffer size. On a slow link (such as a RAS link), if it will take more than five seconds to retrieve data, the Redirector service uses the user's requested buffer size.
ConnectTimeout REG_DWORD Number of seconds
Specifies the maximum amount of time the redirector will wait for a connect or disconnect to complete.
Default: 300 (5 minutes)
LowerSearchBufferSize REG_DWORD Number of kilobytes
Specifies the number of bytes the redirector will use for small searches.
Default: 16K
LowerSearchThreshold REG_DWORD Number of kilobytes
Specifies the number of bytes below which the redirector will request a search of LowerSearchBufferSize. If the search size is larger than this (but below the UpperSearchBufferSize), the redirector will use the UpperSearchBufferSize.
Default: 16K
UpperSearchBufferSize REG_DWORD Number of kilobytes
Specifies the number of bytes the redirector will use for large searches.
Default: 32K
UseAsyncWriteBehind REG_DWORD 0 or 1
Enables the asynchronous-write-behind variation of the write-behind optimization.
Default: 1 (true)
UseWriteBehind REG_DWORD 0 or 1
Enables the write-behind optimization.
Default: 1 (true)