Set index page page compression on by default and remove innodb_trim_pct

as it is not used/implemented.

storage/innobase/handler/ha_innodb.cc

@@ -16786,15 +16786,17 @@ static MYSQL_SYSVAR_BOOL(trx_purge_view_update_only_debug,
   NULL, NULL, FALSE);
 #endif /* UNIV_DEBUG */
 
+/*
 static MYSQL_SYSVAR_LONG(trim_pct, srv_trim_pct,
   PLUGIN_VAR_OPCMDARG ,
   "How many percent of compressed pages should be trimmed",
   NULL, NULL, 100, 0, 100, 0);
+*/
 
 static MYSQL_SYSVAR_BOOL(compress_index_pages, srv_page_compress_index_pages,
   PLUGIN_VAR_OPCMDARG,
-  "Use page compression for only index pages.",
-  NULL, NULL, FALSE);
+  "Use page compression for only index pages. Default TRUE.",
+  NULL, NULL, TRUE);
 
 static MYSQL_SYSVAR_BOOL(use_trim, srv_use_trim,
   PLUGIN_VAR_OPCMDARG,
@@ -16974,7 +16976,7 @@ static struct st_mysql_sys_var* innobase_system_variables[]= {
   MYSQL_SYSVAR(limit_optimistic_insert_debug),
   MYSQL_SYSVAR(trx_purge_view_update_only_debug),
 #endif /* UNIV_DEBUG */
-  MYSQL_SYSVAR(trim_pct),
+  // MYSQL_SYSVAR(trim_pct),
   MYSQL_SYSVAR(compress_index_pages),
   MYSQL_SYSVAR(use_trim),
 #ifdef HAVE_LZ4

storage/innobase/srv/srv0srv.cc

@@ -148,7 +148,7 @@ UNIV_INTERN my_bool	srv_use_native_aio = TRUE;
 
 /* If this flag is TRUE, then we will use page compression
 only for index pages */
-UNIV_INTERN my_bool	srv_page_compress_index_pages = FALSE;
+UNIV_INTERN my_bool	srv_page_compress_index_pages = TRUE;
 UNIV_INTERN long	srv_trim_pct = 100;
 /* If this flag is TRUE, then we will use fallocate(PUCH_HOLE)
 to the pages */

storage/xtradb/handler/ha_innodb.cc

@@ -17934,10 +17934,12 @@ static MYSQL_SYSVAR_BOOL(use_stacktrace, srv_use_stacktrace,
   "Print stacktrace on long semaphore wait (off by default supported only on linux)",
   NULL, NULL, FALSE);
 
+/*
 static MYSQL_SYSVAR_LONG(trim_pct, srv_trim_pct,
   PLUGIN_VAR_OPCMDARG ,
   "How many percent of compressed pages should be trimmed",
   NULL, NULL, 100, 0, 100, 0);
+*/
 
 static MYSQL_SYSVAR_UINT(compression_level, page_zip_level,
   PLUGIN_VAR_RQCMDARG,
@@ -17947,8 +17949,8 @@ static MYSQL_SYSVAR_UINT(compression_level, page_zip_level,
 
 static MYSQL_SYSVAR_BOOL(compress_index_pages, srv_page_compress_index_pages,
   PLUGIN_VAR_OPCMDARG,
-  "Use page compression for only index pages.",
-  NULL, NULL, FALSE);
+  "Use page compression for only index pages. Default TRUE.",
+  NULL, NULL, TRUE);
 
 static MYSQL_SYSVAR_BOOL(use_trim, srv_use_trim,
   PLUGIN_VAR_OPCMDARG,
@@ -18166,7 +18168,7 @@ static struct st_mysql_sys_var* innobase_system_variables[]= {
   MYSQL_SYSVAR(fake_changes),
   MYSQL_SYSVAR(locking_fake_changes),
   MYSQL_SYSVAR(use_stacktrace),
-  MYSQL_SYSVAR(trim_pct),
+  // MYSQL_SYSVAR(trim_pct),
   MYSQL_SYSVAR(compress_index_pages),
   MYSQL_SYSVAR(use_trim),
 #ifdef HAVE_LZ4

storage/xtradb/srv/srv0srv.cc

@@ -163,7 +163,7 @@ UNIV_INTERN my_bool	srv_use_native_aio = TRUE;
 
 /* If this flag is TRUE, then we will use page compression
 only for index pages */
-UNIV_INTERN my_bool     srv_page_compress_index_pages   = FALSE;
+UNIV_INTERN my_bool     srv_page_compress_index_pages   = TRUE;
 UNIV_INTERN long        srv_trim_pct                    = 100;
 /* Default compression level if page compression is used and no compression
 level is set for the table*/