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Leaked semaphore arrays on X7 database servers lead to database instance startup failure or OEDA step "Create Virtual Machine" failure (Doc ID 2421498.1)

Last updated on JANUARY 29, 2020

Applies to:

Exadata X7-2 Hardware - Version All Versions and later
Exadata X7-8 Hardware - Version All Versions and later
Oracle Exadata Storage Server Software - Version to [Release 12.2]
Information in this document applies to any platform.


On X7-2 and X7-8 Exadata database servers running 18.1.0 through 18.1.6, a third-party tool used by CheckHWnFWProfile leaks one semaphore array per invocation, which is typically once per day.  In an OVM configuration this occurs in dom0 only.  The maximum number of semaphores arrays (semmni) is typically set to 256.  Once the number of allocated semaphores arrays reaches 256, then a variety of failures may occur, such as the following: