Configuring a Snapshot

You can configure the parameters for creating and restoring a snapshot.

  • This feature applies only to clusters of 8.2.0 or later. (For clusters of versions earlier than 8.2.0, only some parameters can be configured.)
  • The parameters take effect on all the snapshot creation and restoration tasks.

Procedure

  1. Log in to the GaussDB(DWS) management console.
  2. In the navigation pane on the left, choose Clusters > Dedicated Clusters.
  3. In the cluster list, click the name of the target cluster. The Cluster Information page is displayed.
  4. Click the Snapshots tab page and click Configure Parameters. All the configurable parameters of the current cluster will be displayed.
  5. Configure parameters as required. For details, see Table 1.

  6. Click Save.

Snapshot parameters

Table 1 Snapshot information

Parameter

Type

Description

Default Value

parallel-process

Backup parameter

Number of concurrent processes on each node during Roach backup.

NOTE:

This parameter can be configured for clusters earlier than 8.2.0.

The value is the number of DNs on the current node.

compression-type

Backup parameter

Compression algorithm.

  • zlib
  • LZ4
NOTE:

This parameter can be configured for clusters earlier than 8.2.0.

LZ4

compression-level

Backup parameter

Compression level. The value range is 0 to 9.

  • 0: fast backup and no compression
  • 9: slow backup and maximum compression
NOTE:

This parameter can be configured for clusters earlier than 8.2.0.

6

buffer-size

Backup parameter

Buffer size of the Roach upload media. The value range is 256 to 16,384, in MB.

256

buffer-block-size

Backup parameter

Data block size of the data file to be read by Roach. The value range is 5,242,880 to 268,435,456, in bytes.

67108864

cpu-cores

Backup parameter

Number of CPU cores that can be used when Roach starts multiple threads concurrently

1/2 of the total number of logical CPU cores on the node

master-timeout

Backup parameter

Timeout period for the communication between the Roach master and agent nodes. The value range is 600 to 3600, in seconds.

3600

max-backup-io-speed

Backup parameter

I/O flow control during Roach backup. The value range is 0 to 2048, in MB/s. The value must be greater than the value of buffer-block-size. The value 0 indicates no limit.

0

backup-mode

Backup parameter

Full backup mode.

  • 0: phase-1 backup
  • 1: phase-2 backup

0

cbm-parse-mode

Backup parameter

Incremental backup mode.

  • 0: one-time CBM scan (high memory usage and high performance)
  • 1: multiple CBM scans (stable memory usage and low performance)

0

parallel-process

Restoration parameter

Number of concurrent processes on each node during Roach backup. By default, the value is the number of primary DNs on the current node plus 1.

1

cpu-cores

Restoration parameter

Number of CPU cores that can be used when Roach starts multiple threads concurrently

The default value is 1/2 of the number of CPU cores.

logging-level

Restoration parameter

Log levels:

  • FATAL: Unrecoverable faults that cause the system suspension. This is the most severe level.
  • ERROR: Major errors.
  • WARNING: Exceptions. In this case, the system may continue to process tasks.
  • INFO: Notes.
  • DEBUG: Debugging details.
  • DEBUG2: Detailed debugging information, which is generally not displayed. This is the least severe level.

INFO
Parent topic: Snapshots