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0 votes
2 answers
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Oracle 9i to 12c Replication
I have an old Oracle Forms solution that accesses a 9i database and I have been asked if it's possible to replicate to an Oracle 12c database server, with the intention of using Fusion until a new application is built. Is it possible to replicate between these two versions? Or is there another way t...
I have an old Oracle Forms solution that accesses a 9i database and I have been asked if it's possible to replicate to an Oracle 12c database server, with the intention of using Fusion until a new application is built. Is it possible to replicate between these two versions? Or is there another way to achieve an active-active replica between the two servers? i.e. log shipping etc.
TaylorN (145 rep)
Jul 31, 2019, 03:06 AM • Last activity: Aug 1, 2019, 06:12 AM
6 votes
4 answers
43151 views
MySQL using too much CPU
I'm studying to be a DBA right now because I have a massive live database that is very sensitive that I manage. Here's the current system stats of my dedicated database server: - CentOS 5.9 - 24gb Ram - 8 Core CPU - 50gb FusionIO disk for /var/lib/mysql - MySQL 5.5.23 top - 18:40:27 up 14 days, 4:43...
I'm studying to be a DBA right now because I have a massive live database that is very sensitive that I manage. Here's the current system stats of my dedicated database server: - CentOS 5.9 - 24gb Ram - 8 Core CPU - 50gb FusionIO disk for /var/lib/mysql - MySQL 5.5.23 top - 18:40:27 up 14 days, 4:43, 1 user, load average: 19.72, 22.62, 24.04 Tasks: 183 total, 3 running, 180 sleeping, 0 stopped, 0 zombie Cpu(s): 69.9%us, 0.4%sy, 0.0%ni, 29.2%id, 0.0%wa, 0.1%hi, 0.4%si, 0.0%st Mem: 24685224k total, 20172096k used, 4513128k free, 343420k buffers Swap: 2007284k total, 0k used, 2007284k free, 729004k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 5446 mysql 15 0 18.4g 17g 6176 R 765.8 76.2 114437:38 mysqld I'm currently using 43gb of that 50gb FusionIO slice. MySQL averages around 700 QPS and 75-90% CPU usage. Here's my my.cnf file: [mysqld] user=mysql datadir=/var/lib/mysql socket=/var/lib/mysql/mysql.sock #innodb #innodb_log_file_size = 256M #innodb_log_buffer_size = 8M innodb_flush_log_at_trx_commit = 2 innodb_lock_wait_timeout=50 innodb_file_per_table innodb_buffer_pool_size=16G innodb_buffer_pool_instances=4 #eliminating double buffering innodb_flush_method = O_DIRECT flush_time=86400 skip-name-resolve query_cache_limit=4M query_cache_size=256M sort_buffer_size=8M read_rnd_buffer_size=1M max_connections=5000 interactive_timeout=60 wait_timeout=300 connect_timeout=30 thread_cache_size=32 key_buffer=124M tmp_table_size=4096M max_heap_table_size=256M join_buffer=16M max_connect_errors=2000 table_cache=2048 thread_concurrency=12 long_query_time=5 log-slow-queries=/var/log/mysql-slow.log #table_definition_cache=384 max_allowed_packet=1024M #server-id=20 #log-bin=mysql-bin #expire_logs_days=10 event_scheduler=ON [mysqld_safe] log-error=/var/log/mysqld.log pid-file=/var/run/mysqld/mysqld.pid can you guys recommend any config changes I should make to MySQL or CentOS that can greatly reduce my CPU usage? Or for that matter any other resource improvements?
Logan Best (197 rep)
Jun 19, 2013, 10:53 PM • Last activity: Feb 22, 2018, 03:45 PM
3 votes
1 answers
748 views
MySQL / Fusion IO Configuration Question
I need a little configuration optimization. I think what I have is pretty good but feel like there's still room for improvement. **Current Config** [mysqld] user=mysql datadir=/var/lib/mysql socket=/var/lib/mysql/mysql.sock #innodb innodb_log_file_size = 256M innodb_log_buffer_size = 32M innodb_read...
I need a little configuration optimization. I think what I have is pretty good but feel like there's still room for improvement. **Current Config** [mysqld] user=mysql datadir=/var/lib/mysql socket=/var/lib/mysql/mysql.sock #innodb innodb_log_file_size = 256M innodb_log_buffer_size = 32M innodb_read_io_threads=8 innodb_write_io_threads=8 innodb_flush_log_at_trx_commit = 2 innodb_lock_wait_timeout=50 innodb_file_per_table innodb_buffer_pool_size=16G innodb_buffer_pool_instances=8 innodb_io_capacity=10000 #eliminating double buffering innodb_flush_method = O_DIRECT flush_time=86400 # Disabling symbolic-links is recommended to prevent assorted security risks; # to do so, uncomment this line: # symbolic-links=0 #tmpdir=/dev/shm #tmpdir=/usr/tmpfs skip-name-resolve #skip-locking #safe-show-database query_cache_limit=4M query_cache_size=256M sort_buffer_size=8M read_rnd_buffer_size=1M max_connections=5000 interactive_timeout=60 wait_timeout=300 connect_timeout=30 thread_cache_size=32 key_buffer=124M tmp_table_size=4096M max_heap_table_size=256M join_buffer=16M max_connect_errors=2000 table_cache=2048 thread_concurrency=12 long_query_time=5 log-slow-queries=/var/log/mysql-slow.log #table_definition_cache=384 max_allowed_packet=1024M #server-id=20 #log-bin=mysql-bin #expire_logs_days=10 event_scheduler=ON #master-host = #master-user = #master-password = #master-port = 3306 [mysqld_safe] log-error=/var/log/mysqld.log pid-file=/var/run/mysqld/mysqld.pid **Dedicated Database server specs** - VMWare VM - Dual Quad Xeon X5680 @ 3.33GHz (8 vCPU) - 24gb RAM - Fusion IO mounted on /var/lib/mysql - Rough total of 500 tables between all databases I know this kind of question really kind of requires eyes on the database server but I will gladly append information to this question as needed in order to get a much better configuration. Thanks for the help in advance.
Logan Best (197 rep)
Aug 25, 2013, 09:07 PM • Last activity: Oct 2, 2014, 04:01 PM
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