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Posted by Serverplan, 05-22-2007, 01:18 PM Hi i have a high server load and the cause seem to be the change_db function as i see on the Cacti Graph report, below u can find mytop that report 250qps but in the result is show only 2 query??! why? MySQL on localhost (4.1.21-standard-log) up 0+03:06:28 [19:12:02] Queries: 3.0M qps: 277 Slow: 188.0 Se/In/Up/De(%): 87/00/04/01 qps now: 246 Slow qps: 0.0 Threads: 2 ( 1/ 23) 70/01/03/02 Cache Hits: 2.4M Hits/s: 223.0 Hits now: 156.5 Ratio: 92.0% Ratio now: 90.9% Key Efficiency: 99.9% Bps in/out: 40.6k/319.9k Now in/out: 29.8k/302.4k Id User Host/IP DB Time Cmd Query or State -- ---- ------- -- ---- --- ---------- 56988 root localhost mysql 0 Query show full processlist 57002 freemodd_ localhost freemodd_x 0 Sleep mysql> status; -------------- mysql Ver 14.7 Distrib 4.1.21, for pc-linux-gnu (i686) using readline 4.3 Connection id: 58009 Current database: Current user: root@localhost SSL: Not in use Current pager: stdout Using outfile: '' Using delimiter: ; Server version: 4.1.21-standard-log Protocol version: 10 Connection: Localhost via UNIX socket Server characterset: latin1 Db characterset: latin1 Client characterset: latin1 Conn. characterset: latin1 UNIX socket: /var/lib/mysql/mysql.sock Uptime: 3 hours 9 min 52 sec Threads: 5 Questions: 3145053 Slow queries: 189 Opens: 4998 Flush tables: 1 Open tables: 1024 Queries per second avg: 276.076 -------------- +----------------------------+------------+ | Variable_name | Value | +----------------------------+------------+ | Aborted_clients | 609 | | Aborted_connects | 1048 | | Binlog_cache_disk_use | 0 | | Binlog_cache_use | 0 | | Bytes_received | 472170599 | | Bytes_sent | 3734215665 | | Com_admin_commands | 13 | | Com_alter_db | 0 | | Com_alter_table | 4 | | Com_analyze | 0 | | Com_backup_table | 0 | | Com_begin | 723 | | Com_change_db | 178088 | | Com_change_master | 0 | | Com_check | 0 | | Com_checksum | 0 | | Com_commit | 720 | | Com_create_db | 0 | | Com_create_function | 0 | | Com_create_index | 0 | | Com_create_table | 4 | | Com_dealloc_sql | 0 | | Com_delete | 40980 | | Com_delete_multi | 0 | | Com_do | 0 | | Com_drop_db | 0 | | Com_drop_function | 0 | | Com_drop_index | 0 | | Com_drop_table | 0 | | Com_drop_user | 0 | | Com_execute_sql | 0 | | Com_flush | 4 | | Com_grant | 4 | | Com_ha_close | 0 | | Com_ha_open | 0 | | Com_ha_read | 0 | | Com_help | 0 | | Com_insert | 8632 | | Com_insert_select | 47 | | Com_kill | 6 | | Com_load | 0 | | Com_load_master_data | 0 | | Com_load_master_table | 0 | | Com_lock_tables | 112 | | Com_optimize | 1 | | Com_preload_keys | 0 | | Com_prepare_sql | 0 | | Com_purge | 0 | | Com_purge_before_date | 0 | | Com_rename_table | 0 | | Com_repair | 0 | | Com_replace | 714 | | Com_replace_select | 0 | | Com_reset | 0 | | Com_restore_table | 0 | | Com_revoke | 0 | | Com_revoke_all | 0 | | Com_rollback | 2 | | Com_savepoint | 0 | | Com_select | 219357 | | Com_set_option | 366 | | Com_show_binlog_events | 0 | | Com_show_binlogs | 1 | | Com_show_charsets | 5 | | Com_show_collations | 5 | | Com_show_column_types | 0 | | Com_show_create_db | 0 | | Com_show_create_table | 34 | | Com_show_databases | 19 | | Com_show_errors | 0 | | Com_show_fields | 1224 | | Com_show_grants | 14 | | Com_show_innodb_status | 0 | | Com_show_keys | 0 | | Com_show_logs | 0 | | Com_show_master_status | 0 | | Com_show_ndb_status | 0 | | Com_show_new_master | 0 | | Com_show_open_tables | 0 | | Com_show_privileges | 0 | | Com_show_processlist | 993 | | Com_show_slave_hosts | 0 | | Com_show_slave_status | 85 | | Com_show_status | 647 | | Com_show_storage_engines | 0 | | Com_show_tables | 1294 | | Com_show_variables | 119 | | Com_show_warnings | 0 | | Com_slave_start | 0 | | Com_slave_stop | 0 | | Com_stmt_close | 0 | | Com_stmt_execute | 0 | | Com_stmt_prepare | 0 | | Com_stmt_reset | 0 | | Com_stmt_send_long_data | 0 | | Com_truncate | 0 | | Com_unlock_tables | 112 | | Com_update | 110872 | | Com_update_multi | 86 | | Connections | 58274 | | Created_tmp_disk_tables | 3650 | | Created_tmp_files | 4 | | Created_tmp_tables | 25686 | | Delayed_errors | 0 | | Delayed_insert_threads | 0 | | Delayed_writes | 0 | | Flush_commands | 1 | | Handler_commit | 0 | | Handler_delete | 6221 | | Handler_discover | 0 | | Handler_read_first | 35616 | | Handler_read_key | 20389889 | | Handler_read_next | 18257497 | | Handler_read_prev | 251731 | | Handler_read_rnd | 542275 | | Handler_read_rnd_next | 195694379 | | Handler_rollback | 154 | | Handler_update | 4683591 | | Handler_write | 4967989 | | Key_blocks_not_flushed | 0 | | Key_blocks_unused | 336673 | | Key_blocks_used | 17144 | | Key_read_requests | 36094300 | | Key_reads | 32669 | | Key_write_requests | 115131 | | Key_writes | 27275 | | Max_used_connections | 25 | | Not_flushed_delayed_rows | 0 | | Open_files | 1977 | | Open_streams | 0 | | Open_tables | 1024 | | Opened_tables | 5008 | | Qcache_free_blocks | 6471 | | Qcache_free_memory | 14212384 | | Qcache_hits | 2534160 | | Qcache_inserts | 200351 | | Qcache_lowmem_prunes | 35117 | | Qcache_not_cached | 18627 | | Qcache_queries_in_cache | 20492 | | Qcache_total_blocks | 51334 | | Questions | 3156459 | | Rpl_status | NULL | | Select_full_join | 5108 | | Select_full_range_join | 0 | | Select_range | 14021 | | Select_range_check | 4 | | Select_scan | 65694 | | Slave_open_temp_tables | 0 | | Slave_retried_transactions | 0 | | Slave_running | OFF | | Slow_launch_threads | 0 | | Slow_queries | 189 | | Sort_merge_passes | 0 | | Sort_range | 4752 | | Sort_rows | 1020248 | | Sort_scan | 39925 | | Table_locks_immediate | 536625 | | Table_locks_waited | 1695 | | Threads_cached | 23 | | Threads_connected | 2 | | Threads_created | 25 | | Threads_running | 1 | | Uptime | 11448 | +----------------------------+------------+ my.cnf [mysqld] datadir=/var/lib/mysql socket=/var/lib/mysql/mysql.sock skip-locking #skip-innodb #skip-networking safe-show-database query_cache_limit=1M query_cache_size=96M ## 32MB for every 1GB of RAM query_cache_type=1 max_user_connections=200 max_connections=500 interactive_timeout=10 wait_timeout=20 connect_timeout=20 thread_cache_size=128 key_buffer=384M ## 128MB for every 1GB of RAM join_buffer=1M max_connect_errors=20 max_allowed_packet=16M table_cache=1024 record_buffer=1M sort_buffer_size=3M ## 1MB for every 1GB of RAM read_buffer_size=3M ## 1MB for every 1GB of RAM read_rnd_buffer_size=3M ## 1MB for every 1GB of RAM thread_concurrency=2 ## Number of CPUs x 2 myisam_sort_buffer_size=64M server-id=1 log_slow_queries=/tmp/mysql-slow-queries.log long_query_time=2 collation-server=latin1_general_ci [mysql.server] user=mysql #basedir=/var/lib [safe_mysqld] err-log=/var/log/mysqld.log pid-file=/var/lib/mysql/mysql.pid open_files_limit=8192 [mysqldump] quick max_allowed_packet=16M [mysql] no-auto-rehash #safe-updates [isamchk] key_buffer=64M sort_buffer=64M read_buffer=16M write_buffer=16M [myisamchk] key_buffer=64M sort_buffer=64M read_buffer=16M write_buffer=16M [mysqlhotcopy] interactive-timeout
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