Enforce quota checks after crawl (#10036)

Enforce bucket quotas when crawling has finished. 
This ensures that we will not do quota enforcement on old data.

Additionally, delete less if we are closer to quota than we thought.

cmd/disk-cache-utils.go

@@ -295,6 +295,7 @@ type fileScorer struct {
 	// The list is kept sorted according to score, highest at top, lowest at bottom.
 	queue       list.List
 	queuedBytes uint64
+	seenBytes   uint64
 }
 
 type queuedFile struct {
@@ -337,6 +338,7 @@ func (f *fileScorer) addFileWithObjInfo(objInfo ObjectInfo, hits int) {
 		versionID: objInfo.VersionID,
 		size:      uint64(objInfo.Size),
 	}
+	f.seenBytes += uint64(objInfo.Size)
 
 	var score float64
 	if objInfo.ModTime.IsZero() {
@@ -369,9 +371,14 @@ func (f *fileScorer) addFileWithObjInfo(objInfo ObjectInfo, hits int) {
 
 // adjustSaveBytes allows to adjust the number of bytes to save.
 // This can be used to adjust the count on the fly.
-// Returns true if there still is a need to delete files (saveBytes >0),
+// Returns true if there still is a need to delete files (n+saveBytes >0),
 // false if no more bytes needs to be saved.
 func (f *fileScorer) adjustSaveBytes(n int64) bool {
+	if int64(f.saveBytes)+n <= 0 {
+		f.saveBytes = 0
+		f.trimQueue()
+		return false
+	}
 	if n < 0 {
 		f.saveBytes -= ^uint64(n - 1)
 	} else {