HP jmeter Software for -UX Running, Details, Guidelines, Related Topics, Lock Contention, All remaining cases, already acquired by another thread

Lock Contention	The thread is delayed while attempting to enter a Java monitor that is
	already acquired by another thread.
Running	All remaining cases.

Guidelines

•Large amounts of red in Thread Histogram indicate heavy lock contention, which is usually a possible problem. On the other hand, large amounts of green indicate a potential processing capacity for the involved threads.

•When there is no load, the state for the threads doing the work on behalf of transactions should be waiting, and marked by the green color.

•Threads terminating normally, or because of uncaught exceptions, appear as a discontinued row.

•Multiple short-lived threads appear as apparently blank rows in the display. At the same time the number of displayed threads, shown at the bottom of the display, is large.

•Lock Contention appears as red in the display.

•Deadlocked threads appear as two or more threads spending all their time in lock contention, red, starting from a given time. This point in time identifies the deadlock occurrence.

Details

For each time slice, represented by a small portion of the X-axis, the display along the Y-axis shows the percentage of the time slice that the thread spent in each state. It represents a stacked bar graph for the time slice.

Figure 8-13 Monitoring Metric: Thread Histogram

Related Topics

•Identifying Abnormal Thread Termination (page 44)

•Identifying Multiple Short-lived Threads (page 44)•Identifying Excessive Lock Contention (page 45)•Change Color Selection for Histogram Display (page 185)

132 Using Visualizer Functions