WAS运行问题求解（二）

00000003 TraceResponse W TUNE0214W:The session cache for xxx.war is smaller than the average number of live sessions . Increasing the session cache size to at least 3400.0 may improve performance.

Additional explanatory data follows.

Session cache size (the maxium in memory session count):3,000.

current live sessions:5,000.

Average live sessions over the last sampling interval:3,400.

This alert has been issued 1 time(s) in a row. the threshold will be updated to reduce the overhead of the analysis.

是什么原因引起的？如何消除？