55a64ab8_PHP__Statistics___Manual_mysqlnd_statistics__Result_Set_Description
[Statistic] buffered_sets [Scope] Connection [Notes] Examples of API calls that will buffer result sets on the client: mysql_query(), mysqli_query(), mysqli_store_result(), mysqli_stmt_get_result(). Buffering result sets on the client ensures that server resources are freed as soon as possible and it makes result set scrolling easier. The downside is the additional memory consumption on the client for buffering data. Note that mysqlnd (unlike the MySQL Client Library) respects the PHP memory limit because it uses PHP internal memory management functions to allocate memory. This is also the reason why memory_get_usage() reports a higher memory consumption when using mysqlnd instead of the MySQL Client Library. memory_get_usage() does not measure the memory consumption of the MySQL Client Library at all because the MySQL Client Library does not use PHP internal memory management functions monitored by the function! [Description] 
Number of buffered result sets returned by normal queries. Normal means not prepared statement in the following notes.
PHP: Statistics - Manual
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