Speed up testing (#4239)

* Speed up testing

* make notification run in the background, this recudes the test_readme
time from 18s to 0.10s
* reduce time for zone reload

* TestServeDNSConcurrent remove entirely. This took a whopping 58s for
  ... ? A few minutes staring didn't reveal wth it is actually testing.
  Making values smaller revealed race conditions in the tests. Remove
  entirely.

* Move many interval values to variables so we can reset them to short
  values for the tests.

* test_large_axfr: make the zone smaller. The number used 64K has no
  rational, make it 64/10 to speed up.
* TestProxyThreeWay: use client with shorter timeout

A few random tidbits in other tests.

Total time saved: 177s (almost 3m) - which makes it worthwhile again to
run the test locally:

this branch:

~~~
ok  	github.com/coredns/coredns/test	10.437s
cd plugin; time go t ./...
5,51s user 7,51s system 11,15s elapsed 744%CPU (
~~~

master:

~~~
ok  	github.com/coredns/coredns/test	35.252s
cd plugin; time go t ./...
157,64s user 15,39s system 50,05s elapsed 345%CPU ()
~~~
tests/ -25s
plugins/ -40s

This brings the total on 20s, and another 10s can be saved by fixing
dnstapio. Moving this to 5s would be even better, but 10s is also nice.

Signed-off-by: Miek Gieben <miek@miek.nl>

* Also 0.01

Signed-off-by: Miek Gieben <miek@miek.nl>

1 files changed, 3 insertions, 3 deletions

diff --git a/plugin/file/reload_test.go b/plugin/file/reload_test.go
index 0c644d484..5d712f342 100644
--- a/plugin/file/reload_test.go
+++ b/plugin/file/reload_test.go
@@ -30,9 +30,9 @@ func TestZoneReload(t *testing.T) {
 		t.Fatalf("Failed to parse zone: %s", err)
 	}
 
-	z.ReloadInterval = 500 * time.Millisecond
+	z.ReloadInterval = 10 * time.Millisecond
 	z.Reload(&transfer.Transfer{})
-	time.Sleep(time.Second)
+	time.Sleep(20 * time.Millisecond)
 
 	ctx := context.TODO()
 	r := new(dns.Msg)
@@ -60,7 +60,7 @@ func TestZoneReload(t *testing.T) {
 		t.Fatalf("Failed to write new zone data: %s", err)
 	}
 	// Could still be racy, but we need to wait a bit for the event to be seen
-	time.Sleep(1 * time.Second)
+	time.Sleep(30 * time.Millisecond)
 
 	rrs, err = z.ApexIfDefined()
 	if err != nil {