Performance · Technical

Performance Counters with Threshold values

Counter Description / Thresholds
Memory –
Available Bytes
Description: Available Bytes is the amount of physical memory, in bytes, immediately available for allocation to a process or for system use. It is equal to the sum of memory assigned to the standby (cached), free and zero page lists.
Thresholds: If the average value of the counter is less then 300MB, otherwise the server experiences a performance hit due to memory pressure.
Memory –
Page Faults/sec
Description: This counter gives a general idea of how many times information being requested is not where the application (and VMM) expects it to be. The information must either be retrieved from another location in memory or from the pagefile. Recall that while a sustained value may indicate trouble here, you should be more concerned with hard page faults that represent actual reads or writes to the disk. Remember that the disk access is much slower than RAM.
Thresholds: 0 is the optimum measurement. Any measurement higher than zero delays response time and probably indicates not enough RAM
Memory –
Description: Pages/sec is the rate at which pages are read from or written to disk to resolve hard page faults. This counter is a primary indicator of the kinds of faults that cause system-wide delays.
Thresholds: It should typically be 0–20. (Unhealthy if greater than 80; probably indicates not enough RAM.)
LogicalDisk –
Avg. Disk Bytes/Transfer
Description: Measures the size of input/output (I/O) operations.
To analyze transfer data further, use Avg. Disk Bytes/Read and Avg. Disk Bytes/Write.
– The disk is efficient if it transfers large amounts of data relatively quickly.
– Watch this counter when measuring maximum throughput.
LogicalDisk –
% Free Space
Description: Reports the percentage of unallocated disk space to the total usable space on the logical volume.
PhysicalDisk –
Avg. Disk sec / Transfer
Description: How fast is data being moved (in seconds)? This counter measures the average time of each data transfer, regardless of the number of bytes read or written. It shows the total time of the read or write, from the moment it leaves the Disk Performance Statistics Driver to the moment it is complete.
> 0.3 seconds may indicate disk controller needs too many retrys. Include Faster drives.
PhysicalDisk –
Avg. Disk Bytes/Transfer
< 20K may indicate an app. is accessing too little at a time.
PhysicalDisk –
Current Disk Queue Length
Are disk requests waiting?
Thresholds: If more than 2 request are waiting over time, the disk may be a bottleneck.   More hard drives.
PhysicalDisk –
% Disk Time
Description: How often is the disk busy?
This value is displayed as a percentage and is capped at 100%.
Thresholds: If it’s busy almost all of the time (>90%), and there is a large queue, the disk might be a bottleneck.   More hard drives.
Network Interface –
Output Queue Length
Description: Output Queue Length is the length of the output packet queue (in packets). Since the requests are queued by Network Driver Interface Specification (NDIS) in this implementation, this value is always 0.
Thresholds: If this is longer than 2, there are delays and the bottleneck should be found and eliminated, if possible
Network Interface –
Packets Received/sec
Packets Received/sec is the rate at which packets are received on the network interface.
Network Interface –
Packets Sent/sec
Packets Sent/sec is the rate at which packets are sent on the network interface.
Network Interface –
Packets/sec is the rate at which packets are sent and received on the network interface.
Processor –
% Processor Time
Description: % Processor Time is the percentage of elapsed time that the processor spends to execute a non-Idle thread. It is calculated by measuring the percentage of time that the processor spends executing the idle thread and then subtracting that value from 100%.
– Less than 60% consumed = Healthy
– 51% – 80% consumed = Monitor or Caution
– 81% – 100% consumed = Critical or Out of Spec Scale CPUs
System –
Context Switches/sec
Description: Context Switches/sec is the combined rate at which all processors on the computer are switched from one thread to another. Compare this value with the value of Web Service\Total Method Requests/sec.
– Context switches per request (Context Switches/sec divided by Total Method Requests/sec) should be low.
– high context switches/sec – more than 5000 context switches per second
– Very high context switches/sec – more than 15,000 context switches per second

Reference: Windows 2000 Resource Kit Performance Counters Start Page


2 thoughts on “Performance Counters with Threshold values

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s