Database Management

Reduce the size of the CONV_METRIC_DETAILS tables in the DPA repository

When DPA is monitoring a database instance on a VM with a large number of disks, the CONV_METRIC_DETAIL tables grow rapidly, resulting in a large DPA repository database. If necessary, use one of the resolutions in this article to reduce the size of the repository.

First published date

11/12/2018 9:24 PM

Last published date

4/11/2023 9:48 PM

Overview

When DPA is monitoring a database instance on a VM with a large number of disks, the CONV_METRIC_DETAIL tables grow rapidly, resulting in a large DPA repository database. If necessary, use one of the following resolutions to reduce the size of the repository.

Note: In DPA 2023.2 and later, the vSphere cleaner job and cleans VM disk device metrics are cleaned for for each granularity (seconds, 10 minutes, hours, days). This job ensures that VM data is not retained beyond the specified retention dates. 

Product section

Database Performance Analyzer

Cause

DPA is monitoring a database instance on a VM with a large number of disks.

Resolution

Select one of the following workarounds:

  • Decrease the amount of data being stored
  • Disable VM Disk Device metrics

Decrease the amount of data being stored 

  1. Click Options > Administration > Advanced Options.
  2. Click the VM Options tab and select your vSphere server from the dropdown menu.
  3. Reduce the values of the following parameters:
ParameterDescriptionDefault value
VSPHERE_METRICS_
CLEAN_DAYS_OF_DETAIL		Sets the number of distinct days of vSphere metrics detail data to keep.35
VSPHERE_METRICS_
CLEAN_DAYS_OF_DETAIL_DISK (available in DPA 12.0 and later)

VSPHERE_METRICS_CLEAN_DAYS_OF_DETAIL_DISK is a subset of VSPHERE_METRICS_CLEAN_DAYS_OF_DETAIL and sets the number of distinct days of vSphere metrics disk detail data to keep. Setting this value lower than the  VSPHERE_METRICS_CLEAN_DAYS_OF_DETAIL allows DPA to keep fewer disk metrics while maintaining more days of the non-disk metrics which can help keep the repository size down if DPA is filling up with disk metrics.

You would see the result when you drill down into an hour on a day older than this setting. All other metrics would still be there, but the Storage metrics would not have any data to display.

If VSPHERE_METRICS_CLEAN_DAYS_OF_DETAIL_DISK value is set to a number larger than VSPHERE_METRICS_CLEAN_DAYS_OF_DETAIL, then the VSPHERE_METRICS_CLEAN_DAYS_OF_DETAIL value is used.

35
VSPHERE_METRICS_
CLEAN_DAYS_OF_TEN_MINUTE		Sets the number of distinct days of vSphere metrics ten minute data to keep.35
VSPHERE_METRICS_
CLEAN_DAYS_OF_HOURLY		Sets the number of distinct days of vSphere metrics hourly data to keep.90
VSPHERE_METRICS_
CLEAN_DAYS_OF_DAILY		Sets the number of distinct days of vSphere metrics daily data to keep.1855

Disable VM Disk Device metrics

  1. On the DPA dashboard, click the name of any monitored database instance that collects Disk Device metrics.
  2. Click the Resources tab.
  3. Click the Disk Device tab.
  4. Disable each metric:
    1. Click Settings.
    2. Select Custom.
    3. Clear the Enable Data Collection checkbox.
    4. Click the Save As Default button.

By clicking Save As Default, you disable the metric for all database instances that collect Disk Device metrics.