From: Ben Clewett
Date: May 23 2008 11:48am
Subject: Possible Mutex Problem
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Under 5.0.41 I have having problems of CPU sitting at exactly 100% load 
on a single CPU for very long periods of time, like 10 hours.

I traced this command:

mysql> SHOW MUTEX STATUS;

Which returned 1281006 lines, ending with:

+-------------+------+----------+
| File        | Line | OS_waits |
+-------------+------+----------+
...
...
| buf0buf.c   |  497 |        0 |
| buf0buf.c   |  494 |        0 |
| buf0buf.c   |  497 |        0 |
| buf0buf.c   |  494 |        0 |
| buf0buf.c   |  545 |  1159932 |
| fil0fil.c   | 1293 |      398 |
| srv0start.c | 1201 |        0 |
| srv0start.c | 1194 |        0 |
| srv0start.c | 1172 |        0 |
| dict0mem.c  |   90 |        0 |
| dict0mem.c  |   90 |        0 |
| srv0srv.c   |  875 |    50886 |
| srv0srv.c   |  872 |   113162 |
| thr0loc.c   |  229 |        1 |
| mem0pool.c  |  205 |    25482 |
| sync0sync.c | 1289 |        0 |
+-------------+------+----------+

(All other lines are as same as first two.)

Is there an InnoDB expert who can tell me whether this is indicating a 
problem?

Regards,

Ben