Huge DB2 restore setting

  • 8 December 2023
  • 2 replies

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DB2 backup size is 25TB, separate on 16 disks. I saw below article.

Q1, any suggestion on maximum number of concurrent parallelism queries for my 25TB DB2 restore?

You can improve restore operation performance by using parallelism.

If the database contains a large number of table spaces and indexes, you can perform a restore operation more quickly when you set a maximum number of concurrent parallelism queries. This takes advantage of the available input/output bandwidth and processor power of the DB2 server.

Q2, any suggestion on the number of buffers and buffer size for 25TB DB2 restore?

ou can improve the performance of restore operations of backup images by increasing the number of buffers.

2 replies

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Hi Xiwen,

We are checking this with our internal team and will provide you with the clarification and requirements as soon as we have the information available.

Badge +2

Hi Xiwen,

DB2 database manager automatically uses optimal values (number of buffers, buffer size & parallelism) for efficient use of available resources if they are not tuned manually to provide best performance for large scale databases. 


Optimizing backup performance - IBM Documentation


To manually fine tune the parameters, please refer to the following documentation reference which explains how these values should be calculated: