SNMP Leaks Memory If the OID Cannot Be Decoded

• Microsoft Windows NT Workstation version 4.0
• Microsoft Windows NT Server version 4.0
• Microsoft Windows NT Server version 4.0, Terminal Server Edition

SYMPTOMS

Over time, the Windows NT system responsiveness appears sluggish, and Clients may report a gradual decrease in system performance.

By tracking the amount of Private Bytes for Snmp.exe, it can be observed that, over time, it increases without decreasing. This is viewable using Windows NT Performance Monitor by selecting the following counter to monitor:

Object: Process
Instance: SNMP
Counter: Private Bytes

CAUSE

If SNMP cannot decode an OID from a network packet, SNMP does not free up the memory, resulting in a memory leak in the Snmp.exe processes. The impact of this leak will be more evident on a system running on a network segment that receive lots of SNMP broadcast traffic.

RESOLUTION

To resolve this problem, obtain the latest service pack for Windows NT 4.0 or Windows NT Server 4.0, Terminal Server Edition. For additional information, please see the following article in the Microsoft Knowledge Base:

Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack

STATUS

Microsoft has confirmed this to be a problem in Windows NT 4.0 and Windows NT Server 4.0, Terminal Server Edition. This problem was first corrected in Windows NT 4.0 Service Pack 4.0 and Windows NT Server 4.0, Terminal Server Edition Service Pack 4.

Additional query words: SNMP debug

Keywords : kbnetwork NT4SP4Fix kbbug4.00 kbAPI kbSDKPlatform kbSNMP ntprotocol kbfix4.00.sp4 NTSrvWkst kbGrpNet
Version : WinNT:4.0
Platform : winnt
Issue type : kbbug