REG: Server Service Entries, PART 1

• Windows NT operating system version 3.1
• Windows NT Advanced Server version 3.1

This is the first of two articles on these entries; for the other entries, see "Server Service Entries, Part 2".

SERVER SERVICE ENTRIES

With Registry Editor, you can modify the startup parameters for the Server service. Unless otherwise noted, these parameters are found in this path:

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet
   \Services\LanmanServer\Parameters

This is the first of two articles on these entries; for the other entries, see "Server Service Entries, Part 2".

AlertSched   REG_DWORD   1 to 65535 minutes

Specifies in Microsoft LAN Manager and in Windows NT how often the server checks alert conditions and sends needed alert messages.

Announce   REG_DWORD   1 to 65535 seconds

Specifies how often a nonhidden server announces itself to the network. More frequent announcements keep client server tables more up to date, but cost network overhead and processing on client computers, because clients must process every announcement.

AnnDelta   REG_DWORD   0 to 65535 milliseconds

Specifies the time by which the announcement period can vary. This helps to prevent several servers from continuously announcing simultaneously, thereby reducing network load peaks.

Comment   REG_SZ   Text string

Provides the server’s comment. This is sent in announcements and returned to NetServerGetInfo requests.

Disc   REG_DWORD   0 to infinite minutes

Specifies the amount of idle time that a circuit is allowed before being disconnected. If the virtual circuit has any open files or searches, it is not automatically disconnected. If this parameter is set to a low value, it saves server resources but hinders performance because of clients’ overhead in reconnecting. This is equivalent to autoDisconnect in Microsoft LAN Manager.

DiskSpaceThreshold   REG_DWORD   0 to 99 percent

Specifies the percentage of free disk space remaining before an alert is sent.

EnableFCBopens   REG_DWORD   0 or 1

Specifies whether MS-DOS File Control Blocks (FCBs) are folded together, so multiple remote opens are performed as a single open on the server. This saves resources on the server.

EnableOplockForceClose   REG_DWORD   0 or 1

If a client has an opportunistic lock (oplock) and does not respond to an oplock break, there are two possible behaviors that this parameter selects:

Value       Meaning

0 (false)   Fail the second open, thereby limiting access to the file.
            (This is typical behavior for a client running LAN Manager
            version 2.0.)

1 (true)    Force closed the open instance of the client that has the
            oplock, risking the loss of cached data. (This is typical
            behavior for a client running LAN Manager version 2.1.)

EnableOplocks   REG_DWORD   0 or 1

Specifies whether the server allows clients to use oplocks on files. Oplocks are a significant performance enhancement, but have the potential to cause lost cached data on some networks, particularly wide-area networks.

EnableRaw   REG_DWORD   0 or 1

Specifies whether the server processes raw Server Message Blocks (SMBs). If enabled, this allows more data to be transferred per transaction and improves performance. However, it is possible that processing raw SMBs can impede performance on certain networks. This parameter is automatically tuned by the server.

EnableSoftCompat   REG_DWORD   0 or 1

Specifies whether the server maps a request to a normal open request with shared-read access when the server receives a compatibility open request with read access. Mapping such requests allows several MS-DOS computers to open a single file for read access. However, this feature can potentially cause functionality problems with some MS-DOS applications.

ErrorThreshold   REG_DWORD   1 to 65535

Sets the number of errors that can occur within an AlertSched interval before the server sends an altert message.

Hidden   REG_DWORD   0 or 1

If this parameter is disabled, the server’s name and comment can be viewed by others on the domain. If enabled, the server’s name and comment will not be announced.

InitConnTable   REG_DWORD   1 to 128

Specifies the initial number of tree connections to be allocated in the connection table. The server automatically increases the table as necessary, so setting the parameter to a higher value is an optimization.

InitFileTable   REG_DWORD   1 to 256

Specifies the initial number of file entries to be allocated in the file table of each server connection.

InitSearchTable   REG_DWORD   1 to 2048

Specifies the initial number of entries in the connection’s search table.

InitSessTable   REG_DWORD   1 to 64

Specifies the initial number of session entries to be allocated in the session table of each server connection.

InitWorkItems   REG_DWORD   1 to 512

Specifies the initial number of receive buffers, or work items, used by the server. Allocating work items costs a certain amount of memory initially, but not as much as having to allocate additional buffers later.

IRPstackSize   REG_DWORD   1 to 12

Specifies the number of stack locations in I/O Request Packets (IRPs) used by the server. It may be necessary to increase this number for certain transports, MAC drivers, or local file system drivers. Each increment costs 36 bytes of memory per work item (that is, #work items * 36 bytes = total memory cost).

LinkInfoValidTime   REG_DWORD   0 to 100,000 seconds

Specifies the amount of time during which the transport link information is still valid. If more than this amount of time has passed since the last query, the server requires transport link information.

MaxFreeConnections   REG_DWORD   2 to 8 items

Specifies the maximum number of free connection blocks maintained per endpoint.

MaxLinkDelay   REG_DWORD   0 to 100,000 seconds

Specifies the maximum time allowed for a link delay. If delays exceed this number, the server disablesraw I/O for this connection.

MaxKeepSearch   REG_DWORD   10 to 10000 seconds

Specifies the maximum time during which an incomplete MS- DOS search will be kept by the server. Larger values ensure better interoperability with MS- DOS utilities such as tree-copy and delete-node. However, larger values can cause unusual local behavior (such as a failure of a local directory-delete operation) and higher memory use on the server.

MaxMpxCt   REG_DWORD   1 to 100 requests

Provides a suggested maximum to clients for the number of simultaneous requests outstanding to this server. A higher value can increase server performance but requires higher use of server work items.

MaxNonpagedMemoryUsage   REG_DWORD   1 MB to infinite bytes

Specifies the maximum size of nonpaged memory that the server can have allocated at any time. Adjust this parameter if you want to administer memory quota control.

MaxPagedMemoryUsage   REG_DWORD   1 MB to infinite bytes

Specifies the maximum size of pageable memory that the server can have allocated at any time. Adjust this parameter if you want to administer memory quota control.

MaxWorkItems   REG_DWORD   1 to 512 items

Specifies the maximum number of receive buffers, or work items, the server can allocate. If this limit is reached, the transport must initiate flow control at a significant performance cost.

MaxWorkItemIdleTime   REG_DWORD   10 to 1800 seconds

Specifies the amount of time that a work item can stay on the idle queue before it is freed.

Reference: "The Windows NT Resource Kit for Operating System Version 3.1".