DOCUMENT:Q234351 TITLE :Memory Leak When Performance Counters Are Not Available PRODUCT :Windows NT PROD/VER:4.0 OPER/SYS:WINDOWS NT KEYWORD :kbbug4.00 kbfix4.00 ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server versions 4.0 SP4, 4.0 SP5 - Microsoft Windows NT Server, Enterprise Edition versions 4.0 SP4, 4.0 SP5 ------------------------------------------------------------------------------- SYMPTOMS ======== When you use a program that attempts to gain access to a performance counter that has not been installed, your computer's performance may degrade or the computer may stop responding (hang) because of a memory leak. For example, if you use the Microsoft Systems Management Server (SMS) 2.0 Healthmon tool on a computer that does not have the Microsoft Simple Network Management Protocol (SNMP) configured, the computer may hang and you may be required to restart your computer periodically. CAUSE ===== This problem occurs because memory is not being deallocated correctly when an attempt is made to write data to the corresponding performance counter that is not available. It may be necessary for you to determine which performance counters your program is attempting to update to ensure their availability. RESOLUTION ========== A supported fix that corrects this problem is now available from Microsoft, but it has not been fully regression tested and should be applied only to systems experiencing this specific problem. If you are not severely affected by this specific problem, Microsoft recommends that you wait for the next Windows NT 4.0 service pack that contains this fix. To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web: http://support.microsoft.com/support/supportnet/default.asp The English version of this fix should have the following file attributes or later: Date Time Size File name Platform ------------------------------------------------------------- 05/12/99 07:59p 43,792 Perfctrs.dll x86 05/12/99 07:57p 60,688 Perfctrs.dll Alpha This hotfix has been posted to the following Internet location as Q234351i.exe (x86) and Q234351a.exe (Alpha): ftp://ftp.microsoft.com/bussys/winnt/winnt-public/fixes/usa/NT40/ hotfixes-postSP5/Perfctrs-fix/ NOTE: If this product was already installed on your computer when you purchased it from the Original Equipment Manufacturer (OEM) and you need this fix, please call the Pay Per Incident number listed on the above Web site. If you contact Microsoft to obtain this fix, and if it is determined that you only require the fix you requested, no fee will be charged. However, if you request additional technical support, and if your no-charge technical support period has expired, or if you are not eligible for standard no-charge technical support, you may be charged a non-refundable fee. For more information about eligibility for no-charge technical support, see the following article in the Microsoft Knowledge Base: Q154871 Determining If You Are Eligible for No-Charge Technical Support WORKAROUND ========== To work around this problem, install the SNMP service on your computer. To do this: 1. Click Start, point to Settings, click Control Panel, and then double-click Network. 2. On the Services tab, click Add, and then double-click SNMP Service. 3. When you are prompted, type the full path to the installation files folder (for example, D:\I386), click Continue, and then click Close. 4. Reinstall the latest Windows NT 4.0 service pack, and then restart the computer. STATUS ====== Microsoft has confirmed this to be a problem in Windows NT 4.0. MORE INFORMATION ================ If you are using the Healthmon tool and you have already installed Windows NT 4.0 Service Pack 4 with the SMS hotfix, you may also experience this problem. For additional information about memory leaks and SNMP, please see the following article in the Microsoft Knowledge Base: Q196270 SNMP Agent Leaks Memory When Queried Additional query words: 4.00 SMS healthmon ============================================================================ THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 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