Low RAM configuration for MySQL and Apache. 
In the low VPS plan (VPS1) there is 256MB RAM only. Sometimes, this amount of memory may be too low for successful operation of the Apache and MySQL, to reduce memory usage Apache and MySQL services should be specifically configured. MySQL Open the MySQL server configuration file:
/etc/my.cnf
and add/replace the following configuration options:
[mysqld] port = 3306 socket = /var/lib/mysql/mysql.sock skip-locking key_buffer = 16K max_allowed_packet = 1M table_cache = 4 sort_buffer_size = 64K read_buffer_size = 256K read_rnd_buffer_size = 256K net_buffer_length = 2K thread_stack = 64K # For low memory, Berkeley DB should not be used so keep skip-bdb uncommented unless required skip-bdb # For low memory, InnoDB should not be used so keep skip-innodb uncommented unless required skip-innodb # Uncomment the following if you are using InnoDB tables #innodb_data_home_dir = /var/lib/mysql/ #innodb_data_file_path = ibdata1:10M:autoextend #innodb_log_group_home_dir = /var/lib/mysql/ #innodb_log_arch_dir = /var/lib/mysql/ # You can set .._buffer_pool_size up to 50 - 80 % # of RAM but beware of setting memory usage too high #innodb_buffer_pool_size = 16M #innodb_additional_mem_pool_size = 2M # Set .._log_file_size to 25 % of buffer pool size #innodb_log_file_size = 5M #innodb_log_buffer_size = 8M #innodb_flush_log_at_trx_commit = 1 #innodb_lock_wait_timeout = 50 [mysqldump] quick max_allowed_packet = 16M [mysql] no-auto-rehash # Remove the next comment character if you are not familiar with SQL #safe-updates [isamchk] key_buffer = 8M sort_buffer_size = 8M [myisamchk] key_buffer = 8M sort_buffer_size = 8M [mysqlhotcopy] interactive-timeout
Apache Make sure that large quantity of Apache processes is not set in Apache httpd.conf configuration file. In example.:
StartServers 1 MinSpareServers 1 MaxSpareServers 5 ServerLimit 50 MaxClients 50 MaxRequestsPerChild 5000
Also, set the KeepAliveTimeout parameter to 2 or 3. Apache configuration file, by default often starts all available Apache modules. In particular, it is often issue with Apache prefork MPM version, so that each Apache process "eats" more and more RAM at a geometric progression. Turn off all unnecessary Apache modules by commenting it. Apache 2.2.X notes Configuration files are probably here: / usr/local/apache2/conf In addition, remove the comments on this line:
# Include conf/extra/httpd-mpm.conf
Then edit the configuration file as described above. Turn off Apache modules and features that you do not need, for example: WebDAV. Also, make sure that during installation you select the correct module af Apache MPM. mpm_prefork is a better choice when you're short of RAM, mpm_worker will use more RAM . eg.:
apt-get install apache2-mpm-prefork
We hope these tips will help you lower your RAM usage and improve work of MySQL and Apache services.