aboutsummaryrefslogtreecommitdiff
path: root/plugin/cache/cache_test.go
diff options
context:
space:
mode:
authorGravatar Tobias Schmidt <tobidt@gmail.com> 2018-01-17 08:35:22 +0100
committerGravatar Miek Gieben <miek@miek.nl> 2018-01-17 07:35:22 +0000
commitdd9fc8962c7f51b358c8c127e3efaece559d81f8 (patch)
treeb1a4e84e76b86eea7e6cf87d10d6c0f2ad945081 /plugin/cache/cache_test.go
parentfe0767987e0887cd0121b800241d3d710273ff3d (diff)
downloadcoredns-dd9fc8962c7f51b358c8c127e3efaece559d81f8.tar.gz
coredns-dd9fc8962c7f51b358c8c127e3efaece559d81f8.tar.zst
coredns-dd9fc8962c7f51b358c8c127e3efaece559d81f8.zip
plugin/cache: Fix prefetching issues (#1363)
* Improve plugin/cache metrics * Add coredns_cache_prefetch_total metric to track number of prefetches. * Remove unnecessary Cache.get() call which would incorrectly increment cache counters. * Initialize all counters and gauges at zero. * Allow prefetching of a single request per ttl The original implementation didn't allow prefetching queries which are only requested once during the duration of a TTL. The minimum amount of queries which had to be seen was therefore capped at 2. This change also implements a real prefetch test. The existing test was a noop and always passed regardless of any prefetch implementation. * Fix prefetching for items with a short TTL The default prefetch threshold (percentage) is 10% of the lifetime of a cache item. With the previous implementation, this disabled prefetching for all items with a TTL < 10s (the resulting percentage would be 0, at which point a cached item is already discarded). This change uses a time based threshold calculation and ensures that a prefetch is triggered at a TTL of 1 at the latest. * Fix wrong duration reporting of cached responses The logging and metrics plugins (among others) included the duration of a cache prefetch in the request latency of client request. This change fixes this wrong reporting and executes the prefetch request in a goroutine in the background.
Diffstat (limited to 'plugin/cache/cache_test.go')
-rw-r--r--plugin/cache/cache_test.go18
1 files changed, 6 insertions, 12 deletions
diff --git a/plugin/cache/cache_test.go b/plugin/cache/cache_test.go
index 7b7c2c6f2..b475f3473 100644
--- a/plugin/cache/cache_test.go
+++ b/plugin/cache/cache_test.go
@@ -9,7 +9,6 @@ import (
"golang.org/x/net/context"
"github.com/coredns/coredns/plugin"
- "github.com/coredns/coredns/plugin/pkg/cache"
"github.com/coredns/coredns/plugin/pkg/response"
"github.com/coredns/coredns/plugin/test"
@@ -149,9 +148,9 @@ func cacheMsg(m *dns.Msg, tc cacheTestCase) *dns.Msg {
}
func newTestCache(ttl time.Duration) (*Cache, *ResponseWriter) {
- c := &Cache{Zones: []string{"."}, pcap: defaultCap, ncap: defaultCap, pttl: ttl, nttl: ttl}
- c.pcache = cache.New(c.pcap)
- c.ncache = cache.New(c.ncap)
+ c := New()
+ c.pttl = ttl
+ c.nttl = ttl
crr := &ResponseWriter{ResponseWriter: nil, Cache: c}
return c, crr
@@ -187,7 +186,7 @@ func TestCache(t *testing.T) {
}
if ok {
- resp := i.toMsg(m)
+ resp := i.toMsg(m, time.Now().UTC())
if !test.Header(t, tc.Case, resp) {
t.Logf("%v\n", resp)
@@ -209,9 +208,7 @@ func TestCache(t *testing.T) {
}
func TestCacheZeroTTL(t *testing.T) {
- c := &Cache{Zones: []string{"."}, pcap: defaultCap, ncap: defaultCap, pttl: maxTTL, nttl: maxTTL}
- c.pcache = cache.New(c.pcap)
- c.ncache = cache.New(c.ncap)
+ c := New()
c.Next = zeroTTLBackend()
req := new(dns.Msg)
@@ -228,11 +225,8 @@ func TestCacheZeroTTL(t *testing.T) {
}
func BenchmarkCacheResponse(b *testing.B) {
- c := &Cache{Zones: []string{"."}, pcap: defaultCap, ncap: defaultCap, pttl: maxTTL, nttl: maxTTL}
- c.pcache = cache.New(c.pcap)
- c.ncache = cache.New(c.ncap)
+ c := New()
c.prefetch = 1
- c.duration = 1 * time.Second
c.Next = BackendHandler()
ctx := context.TODO()