My colleague Jim provides some performance tweaks in his book SuiteCRM For Developers, which is available here and a very good resource for any Suite developers.
I’ve copied the relevant pages here in case they help you
PHP
Installing a PHP opcode cache will increase the performance of all PHP files. These work by caching
the compilation of PHP files resulting in less work on each request. Furthermore SuiteCRM will use
the caching API of some PHP accelerators which will further increase performance. If you are using
Linux then APC is the usual choice. Windows users should check out WinCache2.
MySQL
MySQL is notorious for having small default settings. Fully optimising MySQL is outside the scope
of this book (however checkout mysqltuner.pl for a helpful Perl script which will provide setting
recommendations - note that you should be careful when running files from an unknown source).
One small change that can make a big difference is increasing the innodb_buffer_pool_size.
If you have migrated or imported a significant amount of data it is possible that some tables will be
fragmented. Running OPTIMIZE TABLE tablename can increase performance.
Indexes
Adding indexes on the fields of modules can improve database performance. The core modules
usually have important fields indexed. However if you have created a new module or added new,
often searched fields to a module then these fields may benefit from being indexed.
Config Changes
The following are some config settings that can be used to improve performance. These settings should be set in the config_override.php file. See the chapter on the Config files for
more information.
$sugar_config[‘developerMode’] = false;
Unless you are actively developing on an instance developerMode should be off. Otherwise each
page request will cause cached files to be reloaded.
$sugar_config[‘disable_count_query’] = true;
For systems with large amounts of data the count queries on subpanels used for the pagination
controls can become slow thereby causing the page to be sluggish or outright slow to load. Disabling
these queries can improve performance dramatically on some pages.
$sugar_config[‘disable_vcr’] = true;
By default opening the detail view of a record from the list view will also load the other records in
the list to allow for easy moving through records. If you do not use this feature, or, if loading the
detail view for some records has become slow, you can disable this feature.
$sugar_config[‘list_max_entries_per_page’] = ‘10’;
The number of records shown in each page of the list view can be decreased. This will result in a
slight increase in performance on list view pages.
$sugar_config[‘logger’][‘level’] = ‘fatal’;
Lowering the log level means that there will be less log messages to write to disk on each request.
This will slightly (very slightly) increase performance.