test: make maplinear iterdelete test less flaky
iterdelete's run time varies; occasionally we get unlucky. To reduce spurious failures, average away some of the variation.
On my machine, 8 of 5000 runs (0.15%) failed before this CL. After this CL, there were no failures after 35,000 runs.
I confirmed that this adjusted test still fails before CL 141270043.
LGTM=khr
R=khr
CC=bradfitz, golang-codereviews
https://golang.org/cl/140610043
diff --git a/test/maplinear.go b/test/maplinear.go
index 8cc198b..06da968 100644
--- a/test/maplinear.go
+++ b/test/maplinear.go
@@ -146,15 +146,19 @@
// O(n lg n) time. Fortunately, the checkLinear test
// leaves enough wiggle room to include n lg n time
// (it actually tests for O(n^log_2(3)).
- checkLinear("iterdelete", 10000, func(n int) {
- m := map[int]int{}
- for i := 0; i < n; i++ {
- m[i] = i
- }
- for i := 0; i < n; i++ {
- for k := range m {
- delete(m, k)
- break
+ // To prevent false positives, average away variation
+ // by doing multiple rounds within a single run.
+ checkLinear("iterdelete", 2500, func(n int) {
+ for round := 0; round < 4; round++ {
+ m := map[int]int{}
+ for i := 0; i < n; i++ {
+ m[i] = i
+ }
+ for i := 0; i < n; i++ {
+ for k := range m {
+ delete(m, k)
+ break
+ }
}
}
})
