runtime: soften up hash checks a bit
The hash tests generate occasional failures, quiet them some more.
In particular we can get 1 collision when the expected number is
.001 or so. That shouldn't be a dealbreaker.
Fixes #12311
Change-Id: I784e91b5d21f4f1f166dc51bde2d1cd3a7a3bfea
Reviewed-on: https://go-review.googlesource.com/13902
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
diff --git a/src/runtime/hash_test.go b/src/runtime/hash_test.go
index 6b229bd..579b0e3 100644
--- a/src/runtime/hash_test.go
+++ b/src/runtime/hash_test.go
@@ -74,7 +74,7 @@
pairs := int64(s.n) * int64(s.n-1) / 2
expected := float64(pairs) / math.Pow(2.0, float64(hashSize))
stddev := math.Sqrt(expected)
- if float64(collisions) > expected+SLOP*3*stddev {
+ if float64(collisions) > expected+SLOP*(3*stddev+1) {
t.Errorf("unexpected number of collisions: got=%d mean=%f stddev=%f", collisions, expected, stddev)
}
}
