NDMP MA out of memory

  • KM03716012
  • 28-Sep-2020
  • 05-May-2021

Summary

Taking a NDMP backup with 80 million files fails Review, edited

Error

[Critical] From:

NDMP MA out of memory.

BMA-NDMP@xxx.com "Tape_CIFS_1" Time: 05.08.2020 10:31:42

Cause

RAM on MA server is 64 GB which is enough for backup

The problem was due to the backup need handle a huge number of files

The internal buffers that hold catalog information prior to writing to history was set to default (5) hence it causes issues.

Fix

Set

OB2NDMPCATQUESIZE=1 as this backup contains huge number of files (80 millions)

OB2NDMPMEMONLY=1 as this server has much free ram

OB2BTREEORDER=31: help us reduce the memory consumption of BMA

#  OB2NDMPCATQUESIZE=n
#    Default: 5
#    NDMP MA-specific environment variable.
#    This variable is used to fine-tune memory and disk consumption and overall
#    performance of the NDMP backup. When the variable is set to default, the NDMP MA
#    can process up to 20 million files (in one backup specification) if sufficient
#    system resources are available (approximately 1.9 GB of system memory and 2.8 GB of
#    disk space). If sufficient system memory is available and the number of files in a
#    backup specification is less than 20 million, the variable can be set to a higher
#    value. Increasing the value of the variable will increase the performance of
#    NDMP backups to a certain extent. The value of the variable represents the number of
#    internal buffers that hold catalog information prior to writing it to file history
#    swap files. Memory allocation overhead in kilobytes can be calculated by
#    multiplying the value of the variable by 512.