Page History
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In a typical medium-to-large-scale OLTP environment with a data file size of over 50 GB, this value slowly increases over time in a linear fashion with the population of any available history tables.
Reduce the percentage of data used
If your site experiences a sudden sharp increase in this value of over 10% in an hour, investigate the issue to fully understand the underlying causes which often lead to poor performance. Possible causes include:
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