March 25, 2020 – Alert: Possible Data Integrity Issues after Compaction or Defragmentation
InterSystems has corrected two defects that, in rare circumstances, can result in data integrity corruption after running global compaction, database compaction, or database defragmentation. InterSystems recommends avoiding these utilities until after applying the corrections listed below.
1. The first defect is caused by database compaction, defragmentation, or global compaction, and can result in database corruption. If you have used one of these utilities on a database, InterSystems recommends that you perform an integrity check on it. This will identify any data corruption that has occurred. The correction is RJF424.
This defect has been observed on deployed systems and exists for the following versions:
- All released versions of InterSystems IRIS and IRIS for Health
- Caché/Ensemble versions beginning with 2016.2.0
- All HealthShare products based on the above Data Platforms versions
2. The second defect may occur under extremely rare timing conditions, if processes are modifying (sets/kills) a database concurrently with database compaction or defragmentation. In this case, the processes may either make global updates that are not written to the database or access stale data. There is no way to definitively determine if this has occurred. Global compaction is unaffected by this defect. The correction is RJF423.
This second defect exists in all released versions of all InterSystems products, though it is highly unlikely to have occurred on deployed systems.
Both corrections will be included in all future product releases. They are also available by requesting an Ad hoc distribution from the InterSystems Worldwide Response Center (WRC).
If you have any questions regarding this alert, please contact the Worldwide Response Center.