Oracle 5.0 Reference Manual page 742

read_buffer_size
read_only
read_rnd_buffer_size
record_buffer
relay_log_purge
relay_log_space_limit
slave_compressed_protocol
slave_net_timeout
slave_transaction_retries
slow_launch_time
sort_buffer_size
sync-binlog
sync-frm
table_cache
table_lock_wait_timeout
thread_cache_size
thread_concurrency
thread_stack
time_format
tmp_table_size
transaction_alloc_block_size
transaction_prealloc_size
updatable_views_with_limit
wait_timeout
For a server that is currently running, you can see the current values of its system variables by
mysqld
connecting to it and issuing this statement:
mysql> SHOW VARIABLES;
You can also see some statistical and status indicators for a running server by issuing this statement:
mysql> SHOW STATUS;
System variable and status information also can be obtained using mysqladmin:
shell> mysqladmin variables
shell> mysqladmin extended-status
For a full description of all system and status variables, see
and Section 5.1.6, "Server Status
MySQL uses algorithms that are very scalable, so you can usually run with very little memory.
However, normally you get better performance by giving MySQL more memory.
When tuning a MySQL server, the two most important variables to configure are
[458]
key_buffer_size
set appropriately before trying to change any other variables.
The following examples indicate some typical variable values for different runtime configurations.
• If you have at least 256MB of memory and many tables and want maximum performance with a
moderate number of clients, you should use something like this:
shell> mysqld_safe --key_buffer_size=64M --table_cache=256 \
--sort_buffer_size=4M --read_buffer_size=1M &
• If you have only 128MB of memory and only a few tables, but you still do a lot of sorting, you can use
something like this:
shell> mysqld_safe --key_buffer_size=16M --sort_buffer_size=1M
If there are very many simultaneous connections, swapping problems may occur unless
been configured to use very little memory for each connection.
enough memory for all connections.
• With little memory and lots of connections, use something like this:
Tuning Server Parameters
131072
FALSE
262144
131072
TRUE
0
FALSE
3600
10
2
2097144
0
TRUE
64
50
0
10
262144
(No default value)
33554432
8192
4096
1
28800
Variables".
and [498]. You should first feel confident that you have these
table_cache
722
Section 5.1.4, "Server System
performs better if you have
mysqld
Variables",
has
mysqld