[Minor] Readahead cdb file if possible

diff --git a/src/lua/lua_cdb.c b/src/lua/lua_cdb.c
index 0762c8d359305ccfae37542383707c5595e3ae36..8f13f6ccfabac189e9d027a3936444021baf2c70 100644 (file)
--- a/src/lua/lua_cdb.c
+++ b/src/lua/lua_cdb.c
@@ -72,6 +72,21 @@ lua_cdb_create (lua_State *L)
                        lua_pushnil (L);
                }
                else {
+#ifdef HAVE_READAHEAD
+                       struct stat st;
+                       /*
+                        * Do not readahead more than 100mb,
+                        * which is enough for the vast majority of the use cases
+                        */
+                       static const size_t max_readahead = 100 * 0x100000;
+
+                       if (fstat(cdb_fileno(cdb), &st) != 1) {
+                               /* Must always be true because cdb_init calls it as well */
+                               if (readahead(cdb_fileno(cdb), 0, MIN(max_readahead, st.st_size)) == -1) {
+                                       msg_warn ("cannot readahead cdb: %s, %s", filename, strerror (errno));
+                               }
+                       }
+#endif
                        cdb_add_timer (cdb, ev_base, CDB_REFRESH_TIME);
                        pcdb = lua_newuserdata (L, sizeof (struct cdb *));
                        rspamd_lua_setclass (L, "rspamd{cdb}", -1);