Linked Questions

136
votes
5answers
202k views

Possible to make MySQL use more than one core?

I've been presented with some dedicated MySQL servers that never use more than a single core. I'm more developer than DBA for MySQL so need some help Setup The servers are quite hefty with an OLAP/...
108
votes
5answers
188k views

How to safely change MySQL innodb variable 'innodb_log_file_size'?

So I'm fairly new to tuning InnoDB. I'm slowly changing tables (where necessary) from MyIsam to InnoDB. I've got about 100MB in innodb, so I increased the innodb_buffer_pool_size variable to 128MB: ...
38
votes
2answers
59k views

Multi cores and MySQL Performance

Importance of RAM is an established fact but far less material is available about the importance of cores and multithreading when it comes to the usage of CPU by MySQL. I am talking about the ...
20
votes
2answers
28k views

What to set innodb_buffer_pool and why..?

I have 170GB of InnoDB index and Data. I have to readjust the innodb_buffer_pool size for better performance.The Max table size of a InnoDB table(Index+data) is 28GB. So what should be the optimal ...
19
votes
3answers
18k views

Is innodb_file_per_table advisable?

We have an application where just one of the table will be growing into million of lines but the rest will just below a million. So what is the advice should we go with innodb_file_per_table or leave ...
24
votes
2answers
49k views

How do I shrink the innodb file ibdata1 without dumping all databases?

InnoDB stores all tables in one big file ibdata1. After dropping a big table, the file is keeping its size no matter how big the table was. How can I shrink that file without having to dump and re-...
3
votes
2answers
34k views

MySql - Clean ibdata1

I have a database whose entire size is ~44GB, out of which ibdata1 is ~35GB. That doesnt make sense, since the size of the data shouldn't be more than 10GB. I use the following query to get an ...
10
votes
2answers
20k views

Using multiple cores for single MySQL queries on Debian

I am running a MySQL server for tests on a VM (VMWare) with Debian as guest OS. The guest has four emulated CPU cores, so I set thread_concurrency to four. I am doing expensive joins on large tables, ...
5
votes
1answer
18k views

MySQL 5.5 - Innodb - innodb_log_file_size higher than 4GB combined?

When reading online about innodb_log_file_size, it says The combined size of the log files must be less than 4GB So what happens if it needs to be larger? In books and online, it says to set the ...
10
votes
1answer
8k views

Why mysql 5.5 slower than 5.1 (linux,using mysqlslap)

my.cnf (5.5 and 5.1 is the same) : back_log=200 max_connections=512 max_connect_errors=999999 key_buffer=512M max_allowed_packet=8M table_cache=512 sort_buffer=8M read_buffer_size=8M thread_cache=8 ...
5
votes
2answers
7k views

How much memory do I need for innodb buffer pool?

I read here that You need buffer pool a bit (say 10%) larger than your data (total size of Innodb TableSpaces) On the other hand I've read elswher that innodb_buffer_pool_size must be up to %80 ...
4
votes
1answer
11k views

Move ibdata1, set innodb_data_file_path

I am in a bit of an awkward situation right now. I have a database with a few large InnoDB tables, one of which is about 145 GiB. I have been running a lot of maintenance on this table in particular, ...
3
votes
1answer
2k views

MySQL - Installing InnoDB Plugin

I have a Master/Slave Replication Setup, both servers run MySQL 5.1.61. I want to upgrade the master server to a stronger machine with the following: 2 processors - 6 cores each 48GB of RAM To ...
1
vote
1answer
358 views

For a InnoDB only DB, which of these elements can be removed?

So, I'm trying to set up a Drupal 7 my.conf file that's combining best practices from various performance blogs. I'm realizing though that some of them are older than others, and many aren't assuming ...