From eaaea8eb7d2619c5c53947356a7672f4b174b5bc Mon Sep 17 00:00:00 2001 From: Vasil Dimov Date: Thu, 30 Sep 2010 15:48:44 +0300 Subject: [PATCH] Fix Bug#56340 innodb updates index stats too frequently after non-index updates This is a simple optimization issue. All stats are related to only indexed columns, index size or number of rows in the whole table. UPDATEs that touch only non-indexed columns cannot affect stats and we can avoid calling the function row_update_statistics_if_needed() which may result in unnecessary I/O. Approved by: Marko (rb://466) --- storage/innobase/row/row0mysql.c | 7 ++++++- storage/innodb_plugin/row/row0mysql.c | 7 ++++++- 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/storage/innobase/row/row0mysql.c b/storage/innobase/row/row0mysql.c index 4a834c4efc2..2058363c786 100644 --- a/storage/innobase/row/row0mysql.c +++ b/storage/innobase/row/row0mysql.c @@ -1447,7 +1447,12 @@ run_again: srv_n_rows_updated++; } - row_update_statistics_if_needed(prebuilt->table); + /* We update table statistics only if it is a DELETE or UPDATE + that changes indexed columns, UPDATEs that change only non-indexed + columns would not affect statistics. */ + if (node->is_delete || !(node->cmpl_info & UPD_NODE_NO_ORD_CHANGE)) { + row_update_statistics_if_needed(prebuilt->table); + } trx->op_info = ""; diff --git a/storage/innodb_plugin/row/row0mysql.c b/storage/innodb_plugin/row/row0mysql.c index feeb7fc80b7..813a99049fc 100644 --- a/storage/innodb_plugin/row/row0mysql.c +++ b/storage/innodb_plugin/row/row0mysql.c @@ -1422,7 +1422,12 @@ run_again: srv_n_rows_updated++; } - row_update_statistics_if_needed(prebuilt->table); + /* We update table statistics only if it is a DELETE or UPDATE + that changes indexed columns, UPDATEs that change only non-indexed + columns would not affect statistics. */ + if (node->is_delete || !(node->cmpl_info & UPD_NODE_NO_ORD_CHANGE)) { + row_update_statistics_if_needed(prebuilt->table); + } trx->op_info = "";