Measures reported by SybSegTest
A segment is a label that points to one or more database devices. Segment names are used in create table and create index commands to place tables or indexes on specific database devices. Using segments can improve Adaptive Server performance and give the System Administrator or Database Owner increased control over the placement, size, and space usage of database objects.
If a segment runs out of space, it may no longer be able to accommodate critical database objects such as tables/indexes, and will consequently, hamper the usage of the corresponding databases and adversely impact the performance of the underlying the Syvase server. If this is to be avoided, the space usage of the individual segments should be closely tracked, the segments experiencing a space contention should be rapidly isolated, and more space should be promptly allocated to such segments. This is where the SybSegTest test helps!
This test monitors the space usage of each segment of each database on the Sybase server, and accurately points to those segments that may be running out of space.
The measures made by this test are as follows:
| Measurement |
Description |
Measurement Unit |
Interpretation |
| Total_size |
Indicates the maximum size upto which this segment can grow. |
GB |
|
| Used_size |
Indicates the space used by this segment. |
GB |
A low value is desired for this measure. |
| Reserved_space |
Indicates the amount of space allocated to this segment. |
GB |
|
| Free_space |
Indicates the amount of space that is not used by this segment. |
GB |
A high value is desired for this measure. |
| Pct_used |
Indicates the percentage of space used by this segment. |
Percent |
This measure is the ratio of Used_size over the Total_size of a segment.
A value close to 100% indicates excessive space usage by the segment. Compare the value of this measure across segments to identify that segment which has very little or no space left. You may want to allocate more space to that segment to prevent performance degradations. |
| Pct_free |
Indicates the percentage of free space for this segment. |
Percent |
This measure is the ratio of Free_space over the Total_size of a segment.
A very low value for this measure indicates excessive space usage by the segment. Compare the value of this measure across segments to identify that segment which has very little or no space left. You may want to allocate more space to that segment to prevent performance degradations. |
|