Start a Conversation

Solved!

Go to Solution

1 Rookie

 • 

21 Posts

1522

December 15th, 2021 05:00

Oracle Database Recommended I/O Size on EMC Unity

Hi,

What is recommended value for I/O size for Oracle Database on EMC Unity Hybrid/All-Flash array?

db_file_multiblock_read_count is set to 16 but we have large I/O size on storage and this situation increasing service time and response time. The I/O size is near to 1MB. 

1 Rookie

 • 

21 Posts

May 13th, 2022 05:00

The issue was related to “max_sectors_kb” value on Linux.

I think that EMC should add recommendation value to best practices or connectivity guide for EMC Unity.

Also read my blog post about that: I/O Block Size Best Practice on EMC All Flash/Hybrid Flash Array and Linux (Physical And Virtual) - Davoud Teimouri - Virtualization and Data Center

Moderator

 • 

8.8K Posts

December 15th, 2021 13:00

Hi,

The e-lab navigator could help with having the right configuration https://dell.to/3E0lvb9

You could try 32 or 8, I don’t see any specific official recommendations. Maybe someone else in the community can say what they have set it to.

 

1 Rookie

 • 

21 Posts

December 15th, 2021 20:00

Thank you. Actually archive log LUNs generating large I/O size always and when other disk groups generating larger than 128KB, then LUNs response time will be increased.

I couldn't find root cause of generating large I/O size from archive log disks.

No Events found!

Top