Wait Event: Library cache latch

Wait Event: Library cache latch

Possible Causes:

• The library cache latches protect the cached SQL statements and objects definitions held in the library cache within the shared pool. The library cache latch must be acquired in order to add a new statement to the library cache

Actions:

• Latch is to ensure that the application is reusing as much as possible SQL statement representation. Use bind variables whenever possible in the application
• You can reduce the library cache latch hold time by properly setting the SESSION_CACHED_CURSORS parameter
• Consider increasing shared pool

Ref:

• Larger shared pools tend to have long free lists and processes that need to allocate space in them must spend extra time scanning the long free lists while holding the shared pool latch
• An oversized shared pool can increase the contention for the shared pool latch.

FAQ: What are Latches and What Causes Latch Contention (Doc ID 22908.1)
Database Lock and Latch Information Knowledge Browser Product Page (Doc ID 267887.1)
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