Configuring the Performance Analytics Table Cleaner - Support and Troubleshooting

Configuring the Performance Analytics Table Cleaner Issue  Description The scores in the Performance Analytics module are cleared out on a regular basis to prevent these tables from becoming excessively large after a period of time. The records normally cleared are those Performance Analytics score related records that are older than a specific time as well as score related records in which the related Indicator or Breakdown has been deleted or otherwise removed from the instance.

This article will describe the steps that can be used to modify some of the configuration of the objects and processes that control the cleaning of these Performance Analytics score records.

Procedure To Change the time of day or the frequency the Cleaner runs

One of the things a customer may need to adjust is the time at which this Performance Analytics score cleaner runs. This score cleaner is scheduled, out of the box to run once a day at 5:00 AM GMT. However, this can be configured to occur at some other time or the interval at which this runs can be modified. Perform these steps to review and modify the Data Cleaner job:

Log into the instance with an account having admin rights to the instance.

Using the Menu Navigator, browse to the following location: Performance Analytics -> Automation -> Schedules .

A list of Performance Analytics related Scheduled Jobs will appear. Select the Scheduled Job in the list with the Name Clean PA collections by clicking the information icon to the right of that record.

The Clean PA collection scheduled job record will display.

Various fields related to this record can be modified from the form, but it is recommended that most of the fields be left as is. However, in some cases, the Trigger type or Run time field may need to be changed.

The Trigger type determines the frequency for which this Scheduled Job should run. A range of selections can be selected from daily to a specific day in a month in a year, to a run of one time. Based on the option selected, additional fields may appear (such as the day of the month to run for selection of some of the month type options). The out of box setting is daily, such that the job will run every day, and because it runs frequently, will have fewer rows to remove each time it runs.

The Run time is the specific time in the day at which the job should begin running. This is formatted in a glide_time filed, which has respective text boxes for Hour, Minute and Second for which it should run. The default setting for this field is 5:00 AM GMT (which will probably show translated to local time). This time is usually ok, but if for any reason a different time should be selected, this value can be changed by typing in an appropriate Hour, Minute, and Second. Remember to enter the time in your own local time. This time will be stored in GMT time but will display in a users local time.

One thing to keep in mind when setting this field is that the Clean PA collections scheduled job should not be configured to run at the same time as any other Performance Analytics data collection jobs. Thus, this run time time may need to be adjusted to allow for other Performance Analytics jobs to complete. The default times for this and the out-of-box Data Collection jobs are configured so as not to overlap, but if additional data collection jobs have been created or the run times on existing records has been changed, this may need to be changed to prevent overlap of running jobs.

To change the length of time the Performance Analytics Scores or Snapshots are retained

The time period for which Performance Analytics scores are retained can also be changed. The retention period is dependent on a specific system property and is also based on the frequency of the indicator that collects the data associated to that score.

Important!

Please keep in mind system properties can be overridden on the indicator level. Docs:

https://docs.servicenow.com/bundle/sandiego-now-intelligence/page/use/performance-analytics/task/t_CreateAnAutomatedIndicator.html

There are actually two retention periods that should be kept in mind. There is the retention period for the values in the [pa_scores] tables (the scores associated to the specific Indicators) as well as the values in the [pa_snapshots] table (this is the specific sys_id's of the records that fulfill the criteria for the count stored in the corresponding [pa_scores] table. In general because the [pa_snapshots] record will contain more data (which could conceivably be a long string of sys_id's), the retention period for the [pa_snapshots] table is shorter than that as configured for the [pa_scores] tables.

To modify these retention periods, the following steps can be performed:

To begin, say we want to modify the retention periods for the pa_scores records. First, we would log into the instance with an account having admin or pa_admin rights to the instance.

Once logged in, we would browse to the following location: Performance Analytics -> System -> Properties .

A properties page will appear containing many of the Performance Analytics properties on the instance. Locate the property that begins with the heading " Maximum number of periods prior to today for which scores are collected and kept. "

Notice that this value setting shows as a semi-colon delimited list of numerical values. As described in the full property description on that properties page, each of these values in the field corresponds to a particular type of Indicator collection period, as configured for the Indicator as follows: Daily; Weekly; Bi-weekly; Four week; Monthly; Bi-monthly; Quarterly; Fiscal quarter; Half-yearly; Yearly; Fiscal year. Thus, the first value in the list will apply to the score retention period for any Indicator which specifies a Daily collection period, the second value applied to any Indicators using a weekly collection period, etc. The default out-of-box values for this property are as follows:

732;105;53;40;60;30;20;20;20;10;10

Thus, as can be seen, with the default value any scores that are associated to a daily collection Indicator are retained for 732 days, any scores that are collected on a weekly basis are retained for 105 weeks, and so on.

To change any or all of these values, locate the corresponding indicator type you want to change and replace the current value in that position with the new value for that position. Remember that the value shown will be in the same position as indicated in the list and will be in that same level of time-units (days, weeks, months, years, etc).

Once having made any necessary changes, save the change by clicking one of the the two Save buttons on the form, either at the top or bottom of the properties page.

Note that these values could also be modified directly from the System Properties records list by searching for and directly updating the value field in the sys_properties record with the name com.snc.pa.dc.keep_scores_for.frequency.

Modifying the value for retention of the actual record list corresponding to the scores (stored in the pa_scores table) is done in a similar manner.

Log into the instance with an account having admin or pa_admin rights to the instance.

Using the Menu Navigator, browse to the following location on the instance: Performance Analytics -> System -> Properties.

The Performance Analytics properties page will appear. Locate the property on the page with the header which starts with the text " Maximum number of periods prior to today for which lists of records (snapshots) related to a score are collected and kept. ".

As with the scores retention, the values for this property are stored as s semi-colon delimited list of numerical values. Each value in the list corresponds to a particular Indicator specified collection frequency as follows:

Daily; Weekly; Bi-weekly; Four week; Monthly; Bi-monthly; Quarterly; Fiscal quarter; Half-yearly; Yearly; Fiscal year.

The default out-of-box setting for this property will normally be 183;26;13;10;15;8;5;5;5;3;3 corresponding to a retention policy for the snapshot records of 183 days for daily collected values, 26 weeks for weekly collected values, and so on.

To modify one or more of the values, locate the value in the list corresponding to the Indicator collection period that you want to change and replace the current value in that portion with the new value.

Once having adjusted all the values as necessary, click one of the Save buttons as found on the property page (one at the top of the page and the other at the bottom).

The values as stored for this system property could also be modified directly from the System Properties list by locating the sys_property record with the name com.snc.pa.dc.keep_snapshots_for.frequency and adjusting the value field as necessary.

Note that the new values will thus control all subsequent runs of the Performance Analytic score and snapshot record data cleaner starting with the next run but will not cause any change to previously collected data.

Note also that collection jobs will never collect any data older than specified in these properties for the scores or snapshots tables.

Additional Information For information on how to mass delete Performance Analytics score records, see the following KB article:

KB0720725 - Clearing Performance Analytics Score data