1001 Secrets for Windows NT Registry
(Publisher: 29th Street Press)
Author(s): Tim Daniels
ISBN: 1882419685
Publication Date: 12/01/97

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Services for Macintosh

Services for Macintosh (SFM) lets Macintosh-based computers transparently access Windows NT network shares. You can tune the performance of these connections with registry entries. You should consider adjusting these values if you have a LAN that depends on the responsiveness of Windows NT share access from Macs.

VI-24 The following entries’ values control the amount of paged and nonpaged memory that SFM uses as it processes operations. Under heavy workloads, SFM memory requirements rise, and if it can allocate all the memory it requires in one request, its performance improves. However, raising these values can cause other applications, including Windows NT itself, to be unable to allocate memory when they need to.

Hive: HKEY_LOCAL_MACHINE
Key: System\CurrentControlSet\Services\MacFile\Parameters
Value Name: PagedMemLimit
Data Type: REG_DWORD
Value: 20,000

VI-25 Hive: HKEY_LOCAL_MACHINE
Key: System\CurrentControlSet\Services\MacFile\Parameters
Value Name: NonPagedMemLimit
Data Type: REG_DWORD
Value: 4,000

The value in the first key above sets the paged memory limit; the default is 20,000 K. The second key sets the limit of nonpaged memory; the default is 4,000 K.

Dynamic Host Configuration Protocol

VI-26 Dynamic Host Configuration Protocol (DHCP) dynamically assigns IP addresses from a pool of allowable addresses to other machines on a LAN. This registry entry determines whether the DHCP server logs all IP address assignments to a database file. You can then use this database to track down problems in network configuration or behavior. However, logging each DHCP invocation can significantly reduce system performance. If your DHCP seems to be highly stable, you might consider turning off this flag to improve performance.

Hive: HKEY_LOCAL_MACHINE
Key: System\CurrentControlSet\Services\DhcpServer\Parameters
Value Name: DatabaseLoggingFlag
Data Type: REG_DWORD
Value: 1

The default value of 1 enables DHCP logging; change the value to 0 to disable this feature.

NetBEUI

NetBEUI is a transport that has been migrated forward from LanManager and Windows for Workgroups 3.11. The NetBEUI transport is named NBF in Windows NT.

VI-27 This value controls the time NBF waits before resending Logical Link Control (LLC) messages if they are not acknowledged. You should change this registry entry to raise this value if NBF is running over a slow network.

Hive: HKEY_LOCAL_MACHINE
Key: System\CurrentControlSet\Services\NBF\Parameters
Value Name: DefaultT1Timeout
Data Type: REG_DWORD
Value: <number>

The value specifies, in 100-nanosecond increments, the timeout period for unacknowledged LLC messages. The default is 600 milliseconds.

VI-28 This entry controls the number of LLC frames NBF sends before it stops sending and waits for acknowledgment. On a very reliable system, you can increase this number and improve performance. If your network is less reliable, raising the value is not wise because the performance benefit of raising the value is offset by retry operations.

Hive: HKEY_LOCAL_MACHINE
Key: System\CurrentControlSet\Services\NBF\Parameters
Value Name: LLCMaxWindowSize
Data Type: REG_DWORD
Value: 1

The value sets the number of frames NBF sends before waiting for acknowledgment. The default value is 1.

VI-29 This entry determines the number of times NBF retries a request when it gets a T1 timeout. If your NBF is running on a slow network, you might want to increase this value.

Hive: HKEY_LOCAL_MACHINE
Key: System\CurrentControlSet\Services\NBF\Parameters
Value Name: LLCRetries
Data Type: REG_DWORD
Value: 8

A value of 1 or more sets the number of times NBF retries a request; a value of 0 sets no limit on the number of NBF’s retries. The default value is 8.


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