…: mysql> SET profiling=1; mysql> pager cat > /dev/null mysql> …| +———————-+———-+——-+——-+————–+ | removing tmp table | 0.095135 | 55.10 | 3 | 0.0317116667 | | Copying to tmp table | 0.046175 … | 0.00 | 1 | 0.0000020000 | | logging slow query | 0.000001 | 0.00 | 1 …
Post: Troubleshooting MySQL Memory Usage
March 21, 2012 By 5 Comments
…Tables MEMORY tables can take memory. There are implicit MEMORY tables which are allocated for query execution, which size can be controlled by tmp_table…
Post: Is MySQL 5.6 slower than MySQL 5.5?
February 18, 2013 By 23 Comments
….6 is for such simple workload ? How much of this slowness comes from Performance Schema ? Whenever we get difference higher or…_6_10# sysbench –test=oltp –mysql-socket=/tmp/mysql_sandbox5610.sock –mysql-user=msandbox_rw –mysql-password=msandbox –oltp-table-size=1000000 –num-threads=1 –oltp…
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
… you were using the vanilla MySQL server, you would see an entry like this in the slow query log: # Time: 111229 3… Tmp_tables: 0 Tmp_disk_tables: 0 Tmp_table_sizes: 0 # InnoDB_trx_id: F00 # QC_Hit: No Full_scan: Yes Full_join: No Tmp_table: No Tmp_table_on… 0 0 # Boolean: # Filesort 100% yes, 0% no # Tmp table 100% yes, 0% no # Tmp table on 100% yes, 0% no # String: # Databases wp…
Post: The new cool MySQL patch has landed! Check your queries performance!
October 31, 2007 By 16 Comments
…_examined: 1113 LOGGING OF THE REPLICATED STATEMENTS Normally MySQL will not write into slow log any queries executed by the slave’s…. # QC_Hit: No Full_scan: No Full_join: No Tmp_table: Yes Disk_tmp_table: No # Filesort: Yes Disk_filesort: No Merge_passes: 0… execution Tmp_table will be set. Sometimes that table must be created on disk instead of in memory, in such case Disk_tmp_table will…
Post: Finding what Created_tmp_disk_tables with log_slow_filter
September 22, 2008 By 3 Comments
…| Created_tmp_disk_tables | 74 | | Created_tmp_files | 3 | | Created_tmp_tables | 357 | Luckily this client was running the Percona patched version of MySQL. The microslow…disk temporary storage for intermediate results. SET GLOBAL log_slow_filter:= “tmp_table_on_disk,filesort_on_diskâ€; Wait a …
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
…tmp_tables and Created_disk_tmp_tables, I’ll paste in mysql> show global variables like ‘%table_size%’; +———————+———–+ | Variable_name | Value | +———————+———–+ | max_heap_table_size | 268435456 | | tmp_table…perl mysqlsla -lt slow /path/to/slow.log By default…
Post: Optimizing slow web pages with mk-query-digest
April 7, 2011 By 14 Comments
… are usually interested in queries that are consuming most MySQL time and that’s how mk-query-digest …time=0 and all the eXtra benefits from Percona slow query log patch), I knew some particular pages …% no # QC Hit 78% yes, 21% no # Tmp table 2% yes, 97% no # Tmp table on 0% yes, 99% no # String: # …
Post: Side load may massively impact your MySQL Performance
November 13, 2011 By 7 Comments
…mysql –mysql-host=localhost –mysql-table-engine=innodb –mysql-db=test –oltp-table-name=md_cache_test_small –oltp-table-size=1100000 –mysql-user=msandbox –mysql-password=msandbox –mysql-socket=/tmp/mysql… in memory becomes disk IO bound which can slow it down more than 100 times. The solution …
Post: New SpecJAppServer results at MySQL and Sun.
November 12, 2008 By Leave a Comment
… max_heap_table_size=200M log-output = FILE log-slow-queries=/tmp/mysql-slow.log long_query_time = 1 innodb_data_home_dir = /data/mysql/var… tables use in the benchmarks ? As otherwise you also need to boost tmp_table_size to deal with implicit memory tables. innodb_file_per_table – so I assume storing each table in its own…
