ben-manes / caffeine / #5790

100%

push

github

make CLOCK-Pro's cold hand a setting

A referenced cold page whose test period had ended was given a new
test period with its reference bit still set, so it could later be
promoted to hot. That followed neither the CLOCK-Pro paper, which
resets the bit and moves the page to the list head, nor the author's
clock-pro.c, which replaces the page, and it was the unexplained cause
of 10 of the 39 bundled LIRS cells disagreeing with clock-pro.c.

The paper and its reference disagree on this step, so cold-hand
offers both for CLOCK-Pro and CLOCK-Pro+, as camp.tie-break does for
CAMP: replace, the default, matches clock-pro.c and reset matches the
paper. ClockProReferenceTest pins clock-pro.c's misses on the bundled
LIRS traces. Neither rule wins on hit rate: replace gains 15.4pp on
backf at 500 and reset gains up to 2.5pp on sprite.

4752 of 4810 branches covered (98.79%)

9224 of 9236 relevant lines covered (99.87%)

1.0 hits per line