Linux: DB Processes may hang when running large "dd" to NFS disk, leading to RAC eviction or crash (Doc ID 1512914.1)

Last updated on OCTOBER 13, 2016

Applies to:

Oracle Database - Enterprise Edition - Version 10.2.0.1 and later
Information in this document applies to any platform.

Symptoms

DB processes (or any other OS process) may hang or stall in nfs_wait channel while an OS process is creating a large file over NFS using "dd".

In RAC, this can mean a stalled background process which in turn leads to instance termination or instance eviction.

Changes

Creating a large zero-padded file over NFS using "dd" WITHOUT using the "oflag=direct" option.

eg:

 

Cause

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