# HG changeset patch
# User Sascha L. Teichmann <sascha.teichmann@intevation.de>
# Date 1581276294 -3600
# Node ID ab6eb160cd290dfba0579ad414fda488ce8a7963
# Parent  af38a19f615aaa60cc9ed834c3a86770dd1c6fdd
Sounding result cache: Start background cache cleanup lazily only when the cache is really used.

diff -r af38a19f615a -r ab6eb160cd29 pkg/mesh/cache.go
--- a/pkg/mesh/cache.go	Tue Feb 04 16:29:49 2020 +0100
+++ b/pkg/mesh/cache.go	Sun Feb 09 20:24:54 2020 +0100
@@ -68,13 +68,7 @@
 `
 )
 
-var cache = Cache{
-	entries: map[cacheKey]*cacheEntry{},
-}
-
-func init() {
-	go cache.background()
-}
+var cache Cache
 
 func (c *Cache) background() {
 	for {
@@ -129,6 +123,12 @@
 	c.Lock()
 	defer c.Unlock()
 
+	// Start background cleanup lazily.
+	if c.entries == nil {
+		c.entries = map[cacheKey]*cacheEntry{}
+		go c.background()
+	}
+
 	key := cacheKey{date, bottleneck}
 	entry := c.entries[key]