cache.replace(b.Name, dataUsageRoot, *e)
			bucketCh <- b
		}
	}
	xioutil.SafeClose(bucketCh)

	bucketResults := make(chan dataUsageEntryInfo, len(disks))

	// Start async collector/saver.
	// This goroutine owns the cache.
	var saverWg sync.WaitGroup
	saverWg.Add(1)
	go func() {
		// Add jitter to the update time so multiple sets don't sync up.