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Oracle Enterprise Manager for MySQL Database User's Guide
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7.35 Thread Pool Configuration Metrics

Lists the Thread Pool configuration metrics and provides a brief description of each.

Table 7.35 Thread Pool Configuration Metrics

NameDescription
AlgorithmThis variable controls which algorithm the thread pool plugin uses. A value of 0 (the default) uses a conservative low-concurrency algorithm which is most well tested and is known to produce very good results. A value of 1 increases the concurrency and uses a more aggressive algorithm which at times has been known to perform 5-10% better on optimal thread counts, but has degrading performance as the number of connections increases.
High Priority ConnectionThis variable affects queuing of new statements prior to execution. If the value is 0 (false, the default), statement queuing uses both the low-priority and high-priority queues. If the value is 1 (true), queued statements always go to the high-priority queue.
Max Unused ThreadsThe maximum permitted number of unused threads in the thread pool. This variable makes it possible to limit the amount of memory used by sleeping threads.
Prio Kickup TimerThis variable affects statements waiting for execution in the low-priority queue. The value is the number of milliseconds before a waiting statement is moved to the high-priority queue.
SizeThe number of thread groups in the thread pool. This is the most important parameter controlling thread pool performance. It affects how many statements can execute simultaneously.
Stall LimitThe value is the amount of time a statement has to finish after starting to execute before it becomes defined as stalled, at which point the thread pool permits the thread group to begin executing another statement.