Hi all,
When I running a workload(olio) with MySQL 6.0 falcon engine, I find when time goes the
CPU utilization of MySQL server continue increasing to 100%, while the pressure from
client is almost same. I want to know why this issue is happened, so I collect functions
called number every 30 seconds. By looking the called number trend graph, please see the
detail data and graph in attached excel file.
The following functions called number continue increasing during the run before the CPU
reach 100%.
IndexPage::findSupernode
Cach::fetchPage
evaluate_join_record
Dbb::handoffPage
IndexPage::findNodeInBranch
IndexRootPage::scanIndex
IndexPage::findNodeInLeaf
IndexRootPage::findRoot
findLeaf
StorageTable::indexScan
sub_select
StorageInterface::index_read
Index::scanIndex
join_read_key2
The following functions called number are almost flat during the run before the CPU reach
100%, so we confirm the pressure from client is also same.
do_command
dispatch_command
do_select
JOIN::exec
msyql_parse
mysql_execute_command
mysql_select
handle_select
execute_sqlcom_select
join_read_always_key
IndexRootPage::positionIndex
Index::positionIndex
StorageInterface::index_first
join_read_first
handle_one_connection
The following methods are not called.
Inversion::findRoot
Sensitive_cursor::fetch
sub_select_cache
sub_select_sjm
From call stack, we know do_select will call sub_select, sub_select will call
evaluate_join_record and evaluate_join_record may call sub_select also (call loop).
Starting from sub_select, most of functions are increasing during time. Another
interesting thing is the do_select/sub_select ratio is higher to more than 100, and it
also continues increasing up to 180.
Does anyone have any clue for the sub_select or evaluate_join_record continue increasing
while the pressure is same? If you need more data, please let me know.
Thanks very much,
Xiang
Attachment: [application/vnd.ms-excel] function_count_summary.xls function_count_summary.xls
