RMAN backup performance on NFS storage degraded after the OS upgraded from OEL 8.7 to 8.10

Dear Experts,

The RMAN backup performance was degraded after Oracle Enterprise Linux updated from 8.7 to 8.10.

The observation is the CP and dd commands on the OS are working fine getting a speed of 340m per second, below is the reference.

CP command

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[oracle@]$ du -sh /azureblobp/oracle-backups/PROD/ORA_DAILY_INCR/dd.txt

9.8G /azureblobp/oracle-backups/PROD/ORA_DAILY_INCR/dd.txt

[oracle@]$

[oracle@ ]$ date -u; cp /azureblobp/oracle-backups/PROD/ORA_DAILY_INCR/dd.txt /azureblobp/oracle-backups/PROD/ORA_DAILY_INCR/dd2.txt; date -u;

Fri May 2 11:56:07 UTC 2025

Fri May 2 11:57:04 UTC 2025

dd command

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[oracle@DCPDINTORACB03 dbs]$ date -u; dd if=/dev/zero of=/u01/app/oradata/DG1PARCH/dd.txt bs=1M count=10000 conv=fsync; date -u;