add bufferpool argument: Add a buffer pool (SQL administration API)

Use the add bufferpool argument with the admin() or task() function to create a buffer pool.

Syntax


1  EXECUTE FUNCTION
1 admin
1 task
2  (
2  "add bufferpool" , "page_size"
2  ) ;

1  EXECUTE FUNCTION
1 admin
1 task
2  (
2  "add bufferpool" , "page_size" , "buffers"
2?  , "lrus"?  , "max_dirty"?  , "min_dirty"
2  ) ;
Element Description Key Considerations
buffers The number of buffers. The default is 10000 buffers. Each buffer is the size of the operating system page.
lrus The number of LRU queues. The default is 8. The maximum for 32-bit platforms is 128, and for 64-bit platforms is 512.
max_dirty The percentage of modified pages in the LRU queues at which the queue is cleaned. If a field is specified out of the range of values, the default of 60.00 percent is set.
min_dirty The percentage of modified pages in the LRU queues at which page cleaning is not mandatory. Page cleaners might continue cleaning beyond this point under some circumstances. If a field is specified out of the range of values, the default of 80.00 percent is set.
page_size The page size in KB. The page size must be an integral multiple of the default page size, and cannot be greater than 16 KB. On Windows™, the page size is always 4 KB.

Usage

Use add bufferpool argument to create a buffer pool for a page size that does not already have a buffer pool. All other characteristics of the buffer pool that you create are set to the values of the fields in the default line of the BUFFERPOOL configuration parameter.

This function is equivalent to the onparams -b -g command and the BUFFERPOOL configuration parameter.

Example

The following example adds a buffer pool with a page size of 8 KB:
EXECUTE FUNCTION task("add bufferpool","8");

Example

The following example adds a buffer pool with a page size of 2 KB, 50,000 buffers, 8 LRU queues, an LRU maximum of 60 percent, and an LRU minimum of 50 percent:
EXECUTE FUNCTION task("add bufferpool","2","50000","8","60.0","50.0");