IJ54002: UNEXPECTED LONG WAITER ON PREFETCHLISTMUTEX

APAR status

• Closed as program error.

Error description

• When adjusting number of prefetch threads in a partition,
  unexpected long waiter on PrefetchListMutex could be triggered
  leading to other long waiters and application hang.
  

Local fix

• Perform sequential read on a file with file seize bigger than 2
  times the file system block size
  

Problem summary

• When adjusting number of prefetch threads in a partition,
  unexpected long waiter on PrefetchListMutex could be triggered
  leading to other long waiters and application hang.
  

Problem conclusion

• This problem is fixed in 5.1.9.9
  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:
  Update code to avoid unexpected long waiters that can lead to
  application hang
  
  Work Around:
  Perform sequential read on a file with file seize bigger than 2
  times the file system block size
  
  Problem trigger:
  Changes in number of files concurrently opened by user
  applications
  
  Symptom:
  Hang/Deadlock/Unresponsiveness/Long Waiters
  
  Platforms affected:
  ALL Operating System environments
  
  Functional Area affected:
  All Scale Users
  
  Customer Impact:
  High Importance
  

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