Default Alerts
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      1. ProTop Knowledge Base
      2. ProTop Portal Alerts Dashboard
      3. Default Alerts

      Alert: pctLastX Last fixed extent num > 85

      What does it mean? What do I do about it?

      Example alert from the ProTop Portal:

      What does it mean?

      This alert applies to:

      It tells us that the applicable extent of the named storage area (SAName) has grown beyond 85% utilized.

      NOTE: add "export PCTLASTX=yes" to bin/localenv to enable this for your environment.

      Background for pctLastX and un/capped variable extents

      For an “uncapped” but pre-extended extent (an “x” extent), the pre-extended portion is treated as if it were a fixed extent. If an extent is pre-extended to 1GB and pctLastX is set to fire at 50%, an alert should be thrown at 512MB.

      A “capped” variable extent (an “xv” extent) is treated as if it were a fixed extent, and the cap is considered part of the allocated space. Thus, if an extent is capped at 2GB, we treat it as if it were a 2GB fixed extent—even though, from the OS perspective, it is growing. We do this because, from the db perspective, things will behave the same when it hits that cap as if it were fixed. That is, if no “pure variable” extent is next in line, the db will crash. So if pctLastX is set to alert at 50% when that capped extent grows to 1GB, an alert should fire.

      If an extent has been pre-extended AND it has a cap, we only care about the cap. No alert will be fired for growing beyond the pre-extended size.

      What to do?

      Start by running protop RT, command-key "a", for the dbname given.  It will provide you with a comprehensive view of the state of your database areas.  Look at the %Alloc and %LastX columns and address any at or near 100%.  There may be more than one area exhibiting this state. The alert points you to the first issue it finds.

      Address the issue by adding a new fixed extent and or variable extent before that extent fills (assuming there is no variable extent to grow into) and stalls or crashes the database because it cannot grow.

      Please take a look at this article on Managing extent size for more information.

      If all else fails...

      Contact us at support@wss.com or use the online chat. We'll be happy to help.