Space Management Alerts 

You might see the alerts described here when monitoring your Oracle database.

"[BRCONNECT]" below means that the alert is raised by the BRCONNECT database system check.

"[OPTIONAL]" below means that the alert can be turned off here and shown only in the Health monitoring tree. Such alerts always have corresponding Health alerts, as described in Database Health Alerts.

For more information, see Information on Oracle Database Alerts.

Tablespaces

<tablespace name>

Cause: Tablespace alerts can be raised as follows (data file autoextend is taken into account before alert is raised):

●      Freespace: Amount of freespace in the tablespace

●      Used space: Percentage of used space in the tablespace

●      Status: Tablespace status (online or offline)

Action: Extend the tablespace, if necessary, based on your estimate of anticipated growth.

If you add a tablespace, run the RSDBMON0 report from Transaction SE38 so the new tablespace is recognized and represented as a new node in the Tablespaces subtree.

If you drop a tablespace, delete the node representing that tablespace.

 

Segments

Segments with too few allocatable extents

Cause: The number of segments with too few allocatable extents has exceeded the configured threshold. "Too few" is defined in the properties of another monitor node, "Fewest allocatable extents for a segment." All segments that would raise a yellow or red alert in that node (Fewest allocatable extents for a segment) are counted and included in this node. Only segments in the SAP schema for which PCTINCREASE is set to zero are considered.

Action: To determine which segments are affected, run the analysis method, which will list all segments with fewer allocatable extents than specified in the node’s thresholds. If the NEXT storage parameter for this segment is set too high, decrease it to allow the segment to allocate more extents. If NEXT is set as intended, add another data file to the tablespace or activate the feature to autoextend data files.

The collection method that resides at this node feeds other nodes as well.

Running the collection and analysis methods associated with this node can be very resource intensive if you do not run the BRCONNECT database system check at least once a day.

 

Fewest allocatable extents for a segment

Cause: The smallest number of extents left for any segment has fallen below the configured threshold. Only segments in the SAP schema for which PCTINCREASE is set to zero are considered.

Action: To determine which segments are affected, run the analysis method, which will list all segments with fewer allocatable extents than specified in the node’s thresholds. If the NEXT storage parameter for this segment is set too high, decrease it to allow the segment to allocate more extents. If NEXT is set as intended, add another data file to the tablespace or activate the feature to autoextend data files.

Running the collection and analysis methods associated with this node can be very resource intensive if you do not run the BRCONNECT database system check at least once a day.

 

Segments approaching MAX_EXTENTS

Cause: The number of segments that trigger red or yellow alerts for the node Fewest extents left before max_extents has exceeded the configured threshold.

Action: Increase the segment’s storage parameter MAX_EXTENTS if you expect the segment to grow.

Running the collection and analysis methods associated with this node can be very resource intensive if you do not run the BRCONNECT database system check at least once a day.

 

Fewest extents left before MAX_EXTENTS

Cause: The smallest number of allocatable extents for any segments before MAX_EXTENTS is reached has fallen below the configured threshold.

Action: If you expect the segment to grow and, therefore, allocated more extents, increase the segment’s MAX_EXTENTS storage parameter.

Running the collection and analysis methods associated with this node can be very resource intensive if you do not run the BRCONNECT database system check at least once a day.

 

Most allocated extents in any segment

Cause: The number of allocated extents any segment has exceeded the configured threshold. Having few allocated extents per segment was significant when Oracle’s maximum MAX_EXTENTS value was relatively low based on Oracle’s block size. MAX_EXTENTS can now have a value of “unlimited,” eliminating this concern. Having many extents should not cause problems, assuming none of the segments in this tablespace have PCTINCREASE set to non-zero and that the NEXT storage parameter settings for all segments in this tablespace are either all the same or multiples of one another.

Action: If you prefer segments with fewer allocated extents, you can use BRSPACE to reorganize the object.

 

Segments with non-zero PCTINCREASE

Cause: Segments have a PCTINCREASE value other than zero. Because Oracle now allows a MAX_EXTENTS setting of “unlimited”, setting PCTINCREASE to something other than zero no longer makes sense. Setting PCTINCREASE to non-zero can potentially introduce unnecessary fragmentation into your tablespace. Only segments in the SAP schema are considered.

PCTINCREASE was important when the largest number for MAX_EXTENTS was still relatively small and based on Oracle’s block size. Since you should now always be able to avoid reaching MAX_EXTENTS simply by setting its value high enough, you no longer need PCTINCREASE for allocating larger and larger extents to avoid reaching MAX_EXTENTS. This no longer makes sense since you should always be able to avoid reaching MAX_EXTENTS by simply setting its value high enough.

Action: Evaluate whether the segment’s storage parameter can be set to zero.

 

Segments in wrong tablespace [BRCONNECT] [OPTIONAL]

Cause: A segment is in the wrong tablespace, as raised by the BRCONNECT database check. See condition IN_WRONG_TABLESPACE in BRCONNECT Default Conditions for Database Administration.

Action: Reassign the segment to the correct tablespace using online reorganization with BRSPACE.

The non-standard equivalent to this optional alert is Segment in wrong tablespace in Database Health Alerts.

 

Rollback segment extension failed [BRCONNECT] [OPTIONAL]

Cause: There is the following message in the Oracle alert log:

ORA-01562 Failed to extend rollback segment

The rollback segment named in the alert message tried unsuccessfully to allocate an extent of the size specified by the rollback segment’s NEXT storage parameter. This allocation failed because the rollback segment is stored in a tablespace with no free extent large enough. Since rollback segments should be stored in tablespace PSAPROLL and PSAPUNDO, this is most likely the tablespace affected.

Action: If the rollback segment’s NEXT storage parameter is set higher than intended, decrease its value. Otherwise, use BRSPACE to add a data file to the affected tablespace (most likely PSAPROLL or PSAPUNDO).

The non-standard equivalent to this optional alert is Failed to extend rollback in Database Health Alerts.