Cache Management

 

Select the Cache tab to display a configuration screen that features tuning parameters specific to the RAM caching. Within this screen are the following parameters:

 

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Cache Buffers - Determines the number of buffers that are allocated and used from the Windows operating system for InveStore read and write processes.

 

Approximate Values:

 

 1 Buffer = 64 KB RAM

 

 100 Buffers = 6 MB RAM

 

 1000 Buffers = 60 MB RAM

 

Increasing the Cache Buffers (based on available RAM and PageFile) will improve the overall Read and Write performance of the InveStore v4 system.

 

      Range: 100 1000

      Default: 100

Minimum Cache Page - Future v4 release.

Maximum Cache Page - Future v4 release.

 

File Position Threshold; Block Size Threshold - influence read and write behavior as follows:

 

When reading: if the current file position is greater than or equal to the File Position Threshold, and, the size of the data block being retrieved is greater than or equal to the Block Size Threshold, the data block will not remain in the cache after it is read.

 

When writing: if the current file position is greater than or equal to the File Position Threshold, the data block will not remain in the cache after it is written. Block Size Threshold has no effect on writing.

 

File Position Threshold

 

      Range: 0-4GB

      Default: 1024Kb

 

Block Position Threshold

 

      Range: 4GB

      Default: 0

 

The defaults are 1KB and 0KB, respectively.

 

Commit Threshold - determines how often the background cache thread wakes up and flushes dirty cache buffers. This value, expressed in seconds, should be set according to the needs of your application. A short time interval will flush dirty cache buffers more often and can cause a decrease in performance. Data remains in the cache for a shorter period of time.

 

By selecting a greater time interval, data will flush from the cache less frequently which results in better performance. This however increases the risk of data loss in the event of a system failure because data remains the cache longer. Setting this value too high can also cause periodic slow downs as the cache becomes saturated and a forced flush occurs.

 

      Range: 30 seconds to UINT32_MAX (4 GB)

      Default: 120 seconds