IJ40902: PARALLEL ACCESS A FILE VIA MULTI HARD LINKS MIGHT REPORT E_NOENT

APAR status

• Closed as program error.

Error description

• Error Description:
  
  In AFM cache, when access the same file via multiple hard
  links in parallel,
   it might get ENOENT intermittently as below:
  
  2500087 04:02:10.567384
  open("/first/hard/link/to/a/test/file", O_RDONLY) = -1
  ENOENT (No such file or directory) <0.003869>
  ......
  3177041 05:49:22.517706
  stat("/fourth/hard/link/to/a/test/file",",
  0x7f3ee9482570) = -1 ENOENT (No such file or directory)
  <0.002532>
  
  
  Reported in:
  Spectrum Scale 5.1.2.2 on RHEL7
  
  Known Impact:
  Application failure
  
  Verification steps:
  
  Recovery action:
  N/A
  

Local fix

• N/A
  

Problem summary

• Lookup on hardlinks fails intermittently on AFM cache
  filesets. This is due to a race between multiple
  threads performing the lookup of the same
  hardlink from different directories.
  

Problem conclusion

• This problem is fixed in 5.1.4 PTF 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:
  Lookup on hardlinks now work on AFM cache filesets.
  
  Work around: None
  Problem trigger:
  AFM caching with hardlinks
  Symptom:  Unexpected results
  Platforms affected: All Linux OS environments
  Functional Area affected:  AFM
  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 DME

• Fixed component ID

  5737F34AP

Applicable component levels