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Oracle Linux: EXT4 I/O Performance Degradation After Update to UEKR5 (Doc ID 2892849.1)

Last updated on NOVEMBER 10, 2022

Applies to:

Linux OS - Version Oracle Linux 7.0 to Oracle Linux 7.9 with Unbreakable Enterprise Kernel [5.4.17] [Release OL7 to OL7U9]
Linux x86-64


An Oracle Linux 7 system running UEK4 (4.1.12) and Oracle Database 19c (19.3.0) with database files (datafiles) on EXT4 filesystems.

The system is updated to UEK5 (4.14.35), after which Oracle Database experiences I/O performance degradation.

Running the ps(1) command denotes many oracle Database related processes in an uninterruptible (D) state usually in do_blockdev_direct_io and call_rwsem_down_read_failed e.g.:


 Issue was detected after a kernel upgrade from UEK4 to UEK5, using both Oracle Database versions 12c and 19c.


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