MDEV-32145 Disable read-ahead for temporary tablespace

- Lifetime of temporary tables is expected to be short, it would
seem to make sense to assume that all temporary tablespace pages
will remain in the buffer pool. It doesn't make sense to have
read-ahead for pages of temporary tablespace

storage/innobase/buf/buf0rea.cc

@@ -357,7 +357,8 @@ TRANSACTIONAL_TARGET
 ulint
 buf_read_ahead_random(const page_id_t page_id, ulint zip_size, bool ibuf)
 {
-  if (!srv_random_read_ahead)
+  if (!srv_random_read_ahead || page_id.space() >= SRV_TMP_SPACE_ID)
+    /* Disable the read-ahead for temporary tablespace */
     return 0;
 
   if (srv_startup_is_before_trx_rollback_phase)
@@ -514,8 +515,9 @@ TRANSACTIONAL_TARGET
 ulint
 buf_read_ahead_linear(const page_id_t page_id, ulint zip_size, bool ibuf)
 {
-  /* check if readahead is disabled */
-  if (!srv_read_ahead_threshold)
+  /* check if readahead is disabled.
+  Disable the read ahead logic for temporary tablespace */
+  if (!srv_read_ahead_threshold || page_id.space() >= SRV_TMP_SPACE_ID)
     return 0;
 
   if (srv_startup_is_before_trx_rollback_phase)