Cache

This resource contains monitors specific to the current status of the IIS application cache. The icons of the listed performance counters in the Statistic Name column change colors to reflect the listed counter's current state. Clicking any performance counter in the Statistic Name column takes you to the Performance Counter Details page for that performance counter.

If the value of a listed performance counter crosses the Warning threshold, the chart for the listed counter displays a yellow background. If the value of a listed monitor crosses the Critical threshold, the chart for the listed counter displays a red background. Hovering over any time period within the chart displays detailed information about that time period in the tooltip. Hovering over a counter gives you detailed information about that performance counter.

Counter Expert Knowledge Warn-
ing
Criti-
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Current File Cache Memory Usage

Definition:
This performance counter returns the current number of bytes used for the user-mode file cache.

   

Output Cache Current Memory Usage

Definition:
This performance counter returns the current memory usage by output cache.

   

File Cache Hits %

Definition:
This performance counter returns the ratio of user-mode file cache hits to the total number of cache requests since the service started.

Information:
This counter reflects how well the settings for the IIS file cache are working. A site with mostly static files should have a very high cache hit percentage (70%-85%). If the Kernel: Cache Hits % counter is low, this value should be high. Note that this counter does not include dynamic content, only static files. If your static files are not being cached, you might want to lengthen the activity period for this cache.

Possible problems:
The value returned from Kernel: Cache Hits % is low.

Remediation:
If the value returned from Kernel: Cache Hits % is low, examine your file set and determine why your files are not being cached.

   
Kernel URI Cache Hits %

Definition:
This performance counter returns the ratio of kernel URI cache hits to the total number of cache requests since the service started.

< 90 < 70
Metadata Cache Hits %

Definition:
This performance counter returns the ratio of user-mode metadata cache hits to total number of cache request since the service started.

   
Output Cache Current Hits %

Definition:
This performance counter returns the output cache current hit ratio. The ratio is calculated as (H)/(H+M), where H and M represent Hits and Misses in previous sample intervals, respectively.

   
URI Cache Hits %

Definition:
This performance counter returns the ratio of user-mode URI Cache Hits to the total number of cache requests since the service started.

Information:
If content cannot be cached in the HTTP.sys response cache, the value of this counter should be as high as possible. If your content can be stored in the HTTP.sys response cache, the value of this counter should be low.

   

Zooming

You can have the chart show a predetermined time period of data by clicking on any one of the three Zoom buttons in the head of the Zoom column. Alternatively, you can have the chart show a specific date range by dragging the mouse over an area of the chart. The time and date displayed at the top of the resource shows the amount of data currently loaded into the chart. This can be changed by clicking Edit from within the resource.

The Value from Last Poll column shows the most recent data available for the listed statistic.