commit 242402: "Rework the known mutexes..."

ministat -s 242401.forwarding 242402.forwarding
x 242401.forwarding
+ 242402.forwarding
+---------------------------------------------------------------------------------------+
|            +                                                                          |
|+ +      +  +                                                            x     xx   x x|
|                                                                           |____A____| |
| |_____A_M___|                                                                         |
+---------------------------------------------------------------------------------------+
    N           Min           Max        Median           Avg        Stddev
x   5        417527        420242        418902        419074     1049.7974
+   5        402211        404828        404096        403689     1237.6696
Difference at 95.0% confidence
        -15385 +/- 1673.69
        -3.67119% +/- 0.399377%
        (Student's t, pooled s = 1147.58)