Citrix states in their article: CTX850193

CTX850193 - IMA Service Hangs when Attempting to Stop the Service when Performance Counters are Not Responding or Missing

This document was published at: http://support.citrix.com/kb/entry.jspa?externalID=CTX850193

Document ID: CTX850193, Created on: Sep 11, 2001, Updated: Dec 17, 2003

Products: Citrix MetaFrame XP 1.0 for Microsoft Windows 2000, Citrix MetaFrame XP 1.0 for Microsoft Windows 2003, Citrix MetaFrame XP 1.0 for Microsoft NT 4.0 Server Terminal Server Edition

IMA depends on several performance counters to gather data.
If any of these counters were removed or are not responding. the IMA service may hang when trying to stop the service. Using the Microsoft Windows 2000 Resource Kit, remove counters from the system with the utility called Extensible Performance Counter List.

Both Load Management and Resource Management use performance counters to gather data and to determine the server load. If the counters are removed, or there are problems gathering data, the IMA service may not stop when attempting to stop.

Servers may have some of the following messages in the event viewer:

You may receive the above message when Resource Management is installed.

This error message is received from Performance Monitor when attempting to gather information from terminal services for active and inactive sessions.

See Microsoft TechNet Article Q292548 for information about a problem with terminal services that hang when a WinstationQueryEvent does not get answered.

Q297408 - System Monitor Physical Disk Counter Does Not Show New Dynamic Volumes

Q263221 - Memory Leak in Pdh.dll Querying Performance Counters That Do Not Exist

This what to look for:

The IMA service does not stop properly and has to be stopped. There is a long delay when pressing the plus (+) key in Performance Monitor. The Performance Monitor may even stop responding.

These counters are used for Load Management:

Load Evaluator Rule
Description
Performance Monitor Value
Task Manager
Value

CPU Utilization
Calculates load based on a moving average of total CPU utilization across all processors in the server
TSE: System: % Total Processor Time
Windows 2000 Server: Processor: % Processor Time (_Total)
Performance:
CPU
Utilization

Memory Usage
Calculates load based on virtual and physical memory currently in use.
Memory: % Committed Bytes in Use
Performance: Memory Usage

Context
Switches
Calculates load based on CPU context switches
System: Context Switches/sec
A context switch occurs when the operating system switches from one executing process to another.

Disk Data I/O
Calculates load based on disk I/O throughput in kilobytes
Physical Disk: Disk
Bytes/sec (_Total)
The value used by Disk Data I/O is the total for all disks on the server.

Disk
Operations
Calculates load based on number of disk operations per second
Physical Disk: Disk Writes/sec(_Total)
+ Physical Disk: Disk Reads/sec
(_Total)
The value used by Disk
Operations is the total for all disks on the server.

Page Faults
Calculates load based on number of page faults per second
Memory: Page Faults/sec
A page fault occurs when the operating system accesses physical memory that has been flushed to disk.

Page Swap
Calculates load based on number of page swaps per second
Memory: Pages/sec
A page swap occurs when the operating system swaps physical memory to virtual memory on disk.

The following counters are used for Resource Management.

Counter
Metric
Description

Logical Disk
% Disk Time

% Free Space
Indicates how busy the disks are.

The server is running out of disk space.

Memory
Available Bytes

Pages/sec
Informs the administrator if too much memory is being used.

Pages/sec is the number of pages read from or written to disk to resolve hard page faults.

Network Interface
Bytes Total/sec
Bytes Total/sec is the rate at which bytes are sent and received on the interface, including framing characters.

Paging File
% Usage
The amount of the Page File instance in use in percent.

Processor
% Interrupt Time
% Interrupt Time is the percentage of time the processor spent receiving and servicing hardware interrupts during the sample interval.

System
% Processor Time

Context Switches/sec
% Processor Time is the percentage of time that the processor is executing a non-idle thread.

Context Switches/sec is the combined rate at which all processors on the computer are switched from one thread to another.

Terminal Services
Active Sessions

Inactive Sessions
Number of active Terminal Services sessions.

Number of inactive Terminal Services sessions.