syslog_disk_size

Description

syslog_disk_size specifies the maximum disk space for system logs. When the total size of system logs approaches this limit, the oldest log files, including compressed ones, will be deleted.

Privilege requirements

• Query the parameter

  The sys tenant and all user tenants can query this parameter by using the SHOW PARAMETERS statement or the GV$OB_PARAMETERS view.

• Modify the parameter

  Only the sys tenant can modify this parameter. User tenants cannot modify this parameter.

Attributes

Considerations

• The system log files stored by this parameter include all compressed and uncompressed log files in the {install_path}/log directory.

• The syslog_disk_size parameter is based on the du -sh (disk usage) statistics method, which calculates the total disk block size occupied by all files in the log directory. This is different from the df -h (disk free) statistics method, which displays the usage of the entire disk partition (including metadata and cache), and also counts files that have been deleted but are still being used by processes.

• The relationship between the syslog_disk_size parameter and the max_syslog_file_count parameter:

  1. max_syslog_file_count=0 and syslog_disk_size=0: No log recycling occurs until the disk is full.
  2. max_syslog_file_count=0 and syslog_disk_size>0: When the total log size approaches syslog_disk_size, the oldest log files are deleted to recycle space.
  3. max_syslog_file_count>0 and syslog_disk_size=0: When the number of a certain type of log file exceeds max_syslog_file_count, the oldest log files are deleted to recycle space.
  4. max_syslog_file_count>0 and syslog_disk_size>0: When the number of a certain type of log file exceeds max_syslog_file_count or when the total log size approaches syslog_disk_size, the oldest compressed files are deleted.

Examples

Set the maximum disk space for system logs to 50 GB.

obclient> ALTER SYSTEM SET syslog_disk_size='50GB';

References

• Logs
• Log control methods