Operation aging

If you see operations listed one day but you don't see the same operations listed the next, operation aging is almost certainly the reason. Operation (URL) aging is the process by which the NAM Server limits the number of unique operations it retains in its database.

Why NAM ages out operations

Aging improves reporting by making frequently seen operations more readily viewable in reports, and by deemphasizing less important information.

Aging also improves NAM processing:

  • It reduces the amount of data populating memory cache, so the NAM Server is more responsive and requires less memory.
  • It helps to keep the database at a manageable size.
  • It shortens nightly tasks by reducing the volume of data the NAM Server needs to perform tasks against.

How aging works

  1. Every time a data sample is processed, the NAM Server checks to see how many unique operations (Unique URLs) exist in the database against the number it's configured to automatically retain (RTM_URLAGING_COUNT).

  2. If Unique URLs is greater than RTM_URLAGING_COUNT, the NAM Server checks to see if any operations can be aged.
    An operation can be aged if:

    • The operation isn't statically defined in the NAM Console under URL/Query Monitoring
    • The operation hasn't been reported by the NAM Probe in N number of minutes

    If a URL is used in a business unit definition, it is not aged even if the operation is not present during the period defined in RTM_URLAGING_LIFETIME.

    See Managing operation aging below for instructions on configuring relevant properties.

Operations are aged FIFO (first in, first out).

How reports and metrics are affected

If you see a high volume of operations and you have a relatively low setting for URL count, it is likely that operations age out regularly and become unavailable for reports displaying data for later in the day or in previous days. You do not lose the overall data aggregated at the software service level, just data associated with that operation. Any report based on an operation or set of operations that are candidates to be aged and that cover a date range or date in the past may show different values depending on whether those operations have been aged or not.

Aging may thus lead to apparent inconsistencies in related metrics:

  • Metrics reported per server or per software services may not agree with the metric reported for all operations reported under this server or software service.
  • When metrics reported per business unit are defined with operations
    • Aged operations are not counted within the business unit reported in the Software service, operation, and site data view
    • Aged operations are counted in the Application, transaction, and tier data view

Operations that are not present in traffic for some period of time are no longer displayed on reports if they're based on the following dimensions:

  • Operation
  • Task
  • Module
  • Service

If the business unit definition is based on the above dimensions, the following dimensions also age:

  • Application
  • Transaction
  • Transaction step
  • Tier

Managing operation aging

You can turn aging on and off, and you can tweak the parameters that govern the aging process.

Checking current unique operations

The aging algorithm compares Unique URLs to RTM_URLAGING_COUNT (see below) to determine whether it is time to look for operations that should be aged.

To check the count of unique operations (Unique URLs) in the database

  1. Select Diagnostics > System status in the NAM Server navigation menu.
  2. Scroll to the bottom of the System status report and select the Advanced settings link.
  3. Find the Unique URLs row.

Configuring aging parameters

Check and set aging parameters through the Advanced properties editor on the NAM Server.

  1. Select Tools > Admin console in the NAM Server navigation menu.
  2. Select Advanced properties editor.
  3. Search for the property name:
    • Property: RTM_URLAGING_ENABLE
      Default: ON
      Turns aging on or off. No server restart is needed.
    • Property: RTM_URLAGING_COUNT
      Default: 500 URLs/operations
      Determines the number of operations/URLs stored before aging is triggered. No server restart is needed.
    • Property: RTM_URLAGING_LIFETIME
      Default: 420 minutes (7 hours)
      Determines the lifetime of auto-learned operations/URLs. This is the number of minutes an auto-learned URL has to be inactive before it's removed from the database. This aging is performed for every processed sample. No server restart is needed.
      • If a URL is used in a business unit definition, it is not aged even if the operation is not present during the period defined in RTM_URLAGING_LIFETIME.
    • Property: AMD_STORAGE_PERIOD
      Default: 10 days
      Determines the number of days the NAM Probe stores raw data, with a time resolution of 1 interval. This aging is performed during the nightly tasks.

How to check if an operation has aged out

If your log files go back far enough, you can find the name of the operation there.

  1. Open Tools > Admin console in the NAM Server navigation menu.
  2. Select Browse server log.
  3. Set View to url_aging.
  4. Set Include lines for a search string.
  5. Select Update to search for the operation.
    • To focus on a specific time, you can set Begin and End to timestamps such as 20-01-29 01:25:27.298 (YY-MM-DD HH:MM:SS.sss)