14
votes
4answers
15k views
Possible to make MySQL use more then one core
I've been presented with some dedicated MySQL servers that never use more than a single core. I'm more developer then DBA for MySQL so need some help
Setup
The servers are quite hefty with an ...
48
votes
8answers
21k views
What are the main differences between InnoDB and MyISAM?
What are the main differences between InnoDB and MyISAM?
9
votes
1answer
9k 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 ...
15
votes
6answers
9k views
About single threaded versus multithreaded databases performance
H2 is a single threaded database with a good reputation regarding performance. Other databases are multi-threaded.
My question is: when does a multi-thread database become more interesting than an ...
21
votes
3answers
20k 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:
...
10
votes
2answers
3k views
Why Does the Transaction Log Keep Growing or Run Out of Space?
This one seems to be a common question in most forums and all over the web, it is asked here in many formats that typically sound like this:
In SQL Server -
What are some reasons the ...
3
votes
2answers
1k views
Will these two queries result in a deadlock if executed in sequence?
This is almost certainly the cause of my other question, but I thought it was worth separating the two as I have a hypothesis based on the following log that I would love to have falsified or ...
6
votes
2answers
2k views
Trouble deciphering a deadlock in an innodb status log
We are accessing MySQL from the Microsoft ADO.NET connector.
Occasionally we are seeing the following deadlock in our innodb status and haven't been able to identify the cause of the problem. It ...
9
votes
3answers
10k views
Why does InnoDB store all databases in one file?
It was convenient that MyISAM used to store each table in a corresponding file. InnoDB has made advancements in many aspects, but I wonder why InnoDB stores all databases in one file (ibdata1 by ...
4
votes
1answer
2k 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
...
7
votes
1answer
2k views
Reasons for occasionally slow queries?
We are running MySQL 5.1 on Windows Server 2008 R2.
We have been doing some diagnostics on our database of late and have found some disturbing artifacts which we can't explain. We added some code to ...
2
votes
3answers
2k 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 ...
43
votes
7answers
22k views
How can I optimize a mysqldump of a large database?
I have a symfony application with an InnoDB database that is ~2GB with 57 tables. The majority of the size of the database resides in a single table (~1.2GB). I am currently using mysqldump to ...
32
votes
8answers
2k views
Files - in the database or not?
What is the best place for storing binary files that are related to data in your database? Should you:
Store in the database with a blob
Store on the filesystem with a link in the database
Store in ...
11
votes
2answers
3k views
How do I properly perform a MySQL bake-off?
I want to performance test (aka bake-off) MySQL server rpm against some other forks such as Percona server, MariaDB, and possibly some others. I'm hoping that by asking this question I can better ...
