Info on the technet sites seems pretty lean to me...

Log Name: Application
Source: ESENT
Date: 05/09/2012 06:26:21
Event ID: 910
Task Category: Performance
Level: Warning
Keywords: Classic
User: N/A
Computer: server
Description:
taskhostex (2184) The database cache size maintenance task has taken 60 seconds without completing. This may result in severe performance degradation. Current cache size is 13 buffers above the configured cache limit (121 percent of target). Cache size maintenance evicted 4 buffers, made 16950 flush attempts, and successfully flushed 0 buffers. It has run 3498 times since maintenance was triggered.
Event Xml:



910
3
7
0x80000000000000

239
Application
server



taskhostex
2184


60
13
121
4
16950
0
3498

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