Table of Contents

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  1. Preface
  2. Performance Tuning Overview
  3. Bottlenecks
  4. Optimizing the Target
  5. Optimizing the Source
  6. Optimizing Mappings
  7. Optimizing Transformations
  8. Optimizing Sessions
  9. Optimizing Grid Deployments
  10. Optimizing the PowerCenter Components
  11. Optimizing the System
  12. Using Pipeline Partitions
  13. POWERCENTERHELP
  14. Performance Counters

Performance Tuning Guide

Performance Tuning Guide

Readfromcache and Writetocache Counters

Readfromcache and Writetocache Counters

If a session contains Aggregator, Rank, or Joiner transformations, examine the
Transformation_
readfromcache and
Transformation
_writetocache counters along with the
Transformation_
readfromdisk and
Transformation
_writetodisk counters to analyze how the Integration Service reads from or writes to disk. To view the session performance details while the session runs, right-click the session in the Workflow Monitor and choose Properties. Click the Properties tab in the details dialog box.
To analyze the disk access, first calculate the hit or miss ratio. The hit ratio indicates the number of read or write operations the Integration Service performs on the cache.
The miss ratio indicates the number of read or write operations the Integration Service performs on the disk.
Use the following formula to calculate the cache miss ratio:
[(# of reads from disk) + (# of writes to disk)]/[(# of reads from memory cache) + (# of writes to memory cache)]
Use the following formula to calculate the cache hit ratio:
[1 - Cache Miss ratio]
To minimize reads and writes to disk, increase the cache size. The optimal cache hit ratio is 1.