Queue depth events: example 1
A basic sequence of queue depth events.
Figure 1 shows the variation of queue depth over time.
Commentary
- At T(1), the queue depth is increasing (more MQPUT calls than MQGET calls) and crosses the Queue Depth Low limit. No event is generated at this time.
- The queue depth continues to increase until T(2), when
the depth high limit (80%) is reached and a Queue Depth High event
is generated.
This enables both Queue Full and Queue Depth Low events.
- The (presumed) preventive actions instigated by the event prevent the queue from becoming full. By time T(3), the Queue Depth High limit has been reached again, this time from above. No event is generated at this time.
- The queue depth continues to fall until T(4), when it
reaches the depth low limit (20%) and a Queue Depth Low event is generated.
This enables both Queue Full and Queue Depth High events.
Event statistics summary
Table 1 summarizes the queue event statistics and Table 2 summarizes which events are enabled.
Event 2 | Event 4 | |
---|---|---|
Time of event | T(2) | T(4) |
Type of event | Queue Depth High | Queue Depth Low |
TimeSinceReset | T(2) - T(0) | T(4) - T(2) |
HighQDepth (Maximum queue depth since reset) | 800 | 900 |
MsgEnqCount | 1157 | 1220 |
MsgDeqCount | 357 | 1820 |
Time period | Queue Depth High event | Queue Depth Low event | Queue Full event |
---|---|---|---|
Before T(1) | ENABLED | - | - |
T(1) to T(2) | ENABLED | - | - |
T(2) to T(3) | - | ENABLED | ENABLED |
T(3) to T(4) | - | ENABLED | ENABLED |
After T(4) | ENABLED | - | ENABLED |