- * Ensure we support mutiple get_next / put sequences followed
- * by put_next. The metadata stream lock internally protects
- * reading the metadata cache. It can indeed be read
- * concurrently by "get_next_subbuf" and "flush" operations on
- * the buffer invoked by different processes.
+ * Ensure we support mutiple get_next / put sequences followed by
+ * put_next. The metadata cache lock protects reading the metadata
+ * cache. It can indeed be read concurrently by "get_next_subbuf" and
+ * "flush" operations on the buffer invoked by different processes.
+ * Moreover, since the metadata cache memory can be reallocated, we
+ * need to have exclusive access against updates even though we only
+ * read it.