IJ51344: INCORRECT DATA WRITTEN TO FILE WHEN FILE IS MEMORY-MAPPED

APAR status

• Closed as program error.

Error description

• When writing to a memory-mapped file, there is a chance that
  incorrect data could be written to the file before and after the
  targeted write range
  

Local fix

• Stop using memory-mapping
  

Problem summary

• When writing to a memory-mapped file, there is a chance that
  incorrect data could be written to the file before and after the
  targeted write range
  

Problem conclusion

• This problem is fixed in 5.2.0.1
  To see all Spectrum Scale APARs and their respective
  Fix solutions refer to page: 
  https://public.dhe.ibm.com/storage/spectrumscale/spectrum_scale
  _apars.html
  
  Benefits of the solution:
  Fix the issue so writing to memory-mapped files will ensure only
  correct data are written
  
  Work Around:
  Stop using memory-mapping
  
  Problem trigger:
  Writing to memory-mapped files with offsets and lengths
  unaligned to the internal buffer range size (usually subblock
  size or 4k) could cause incorrect data to be written before and
  after the targeted write range
  
  Symptom:
  Unexpected Results/Behavior
  
  Platforms affected:
  ALL Operating System environments
  
  Functional Area affected:
  All scale users
  
  Customer Impact:
  Critical
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  SPEC SCALE STD

• Fixed component ID

  5737F33AP

Applicable component levels