How can I tell if my DXgrid datastore is filling up, and what can I do when it gets full?

Document ID : KB000053628
Last Modified Date : 14/02/2018
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Description:

When a DXgrid datastore is created, it's size is fixed. It will not automatically increase in size. Therefore, when a DXgrid datastore increases in size past 60% full, there are a variety of alarms that are generated by the DSA informing you to the fact that the data hosted in the DXgrid file is increasing. These alarms will continue to the generated as the datastore fills. The purpose of this techdoc is to inform you of the alarms that you will see and how you can extend the size the of the datastore once it grows to 100% full.

Solution:

When a DXgrid datastore is created, the creation process will read the DXgrid size parameter either from the:

  • DXmanager XML configuration
  • The "dxgrid-db-size" configuration parameter in the ASCII text configuration files (when using DXnewdb)

Once the creation process has read the DXgrid size, it will commence to create the datastore ".db" file on disk There are alarms that will be triggered when a DXgrid datastore grows past 60% full. If the datastore increases past 60% full, the DSA will trigger additional alarms at 10% intervals. So in the DSAs alarm log you will see:

** ALARM **: 60% of datastore in use
** ALARM **: 65% of datastore in use
** ALARM **: 70% of datastore in use
** ALARM **: 75% of datastore in use
** ALARM **: 80% of datastore in use
** ALARM **: 85% of datastore in use
** ALARM **: 90% of datastore in use
** ALARM **: 95% of datastore in use

Once the datastore file space has filled completely, you will see the following ALARMS:

** ALARM **: File space exhausted
** ALARM **: File space exhausted

** FATAL ERROR **: Assertion failed (r:/head.new/src/dsa/dxgrid/caDxgrid.c1861)
** ALARM **: File space exhausted
** ALARM **: File space exhausted
** ALARM **: File space exhausted
** ALARM **: File space exhausted
** ALARM **: File space exhausted

The resolution to this issue is to extend the DXgrid data store. This can be achieved using the DXtool called "dxextenddb". The process for extending a datastore is as follows:

  1. Shutdown the DSA

  2. Edit the dxgrid-db-size parameter within the DSA's initialization file (DXHOME/config/servers/{dsaName.dxi})

  3. Run "dxextenddb {dsaName}"

  4. Restart the DSA

Once the DXgrid datastore has been extended and restarted, you can continue adding or modifying entries.

As an addendum, modifying the trace levels in the DSA's trace logs will provide you with additional information when the datastore is getting full. Setting a trace level of "warn,error" will generate additional information similar to that listed below:

> [1216] set trace=warn,error;
* [3664] 20090114.175413.689 60% of datastore in use
* [5092] 20090114.175414.126 65% of datastore in use
* [5092] 20090114.175414.548 70% of datastore in use
* [1040] 20090114.175415.032 75% of datastore in use
* [5404] 20090114.175415.517 80% of datastore in use
* [3664] 20090114.175415.970 85% of datastore in use
* [3700] 20090114.175416.361 90% of datastore in use
* [3664] 20090114.175416.814 95% of datastore in use
* [1216] 20090114.175417.298 File space exhausted
? [1216] 20090114.175417.298 WARN : Cannot add entry to cache - rolling back
* [5244] 20090114.175417.298 File space exhausted
? [5244] 20090114.175417.298 WARN : Cannot add entry to cache - rolling back
* [3700] 20090114.175417.345 File space exhausted
? [3700] 20090114.175417.345 WARN : Cannot add entry to cache - rolling back
* [1216] 20090114.175417.345 File space exhausted
? [1216] 20090114.175417.345 WARN : Cannot add entry to cache - rolling back
* [1216] 20090114.175417.345 Assertion failed (r:/head.new/src/dsa/dxgrid/caDxgrid.c1861)