Ideal would be to find a reproducible-by-others testcase which does what you
believe to be the wrong thing.
That depends upon whether there are more suitable ways of fixing "the
wrong thing".
There may not be - it could well be that present behaviour
is correct for the testcase, but it leaves the system in the wrong
state for your large workload shift. In that case, prefetching (ie:
restoring system state approximately to that which prevailed prior to
"testcase") might well be a suitable fix.
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