Function fast_load

src/jrd/btr.cpp:3745–4525

static ULONG fast_load(thread_db* tdbb,
					   IndexCreation& creation,
					   SelectivityList& selectivity)
{
/**************************************
 *
 *	f a s t _ l o a d
 *
 **************************************
 *
 * Functional description
 *	Do a fast load.  The indices have already been passed into sort, and
 *	are ripe for the plucking.  This beast is complicated, but, I hope,
 *	comprehendable.
 *
 **************************************/
#ifdef DEBUG_BTR_PAGES
	TEXT debugtext[1024];
#endif

	SET_TDBB(tdbb);
	const Database* const dbb = tdbb->getDatabase();
	CHECK_DBB(dbb);

	jrd_rel* const relation = creation.relation;
	index_desc* const idx = creation.index;
	const USHORT key_length = creation.key_length;

	const USHORT pageSpaceID = relation->getPages(tdbb)->rel_pg_space_id;

	// leaf-page and pointer-page size limits, we always need to
	// leave room for the END_LEVEL node.
	const USHORT lp_fill_limit = dbb->dbb_page_size - BTN_LEAF_SIZE;
	const USHORT pp_fill_limit = dbb->dbb_page_size - BTN_PAGE_SIZE;

	// AB: Let's try to determine to size between the jumps to speed up
	// index search. Of course the size depends on the key_length. The
	// bigger the key, the less jumps we can make. (Although we must
	// not forget that mostly the keys are compressed and much smaller
	// than the maximum possible key!).
	// These values can easily change without effect on previous created
	// indices, cause this value is stored on each page.
	// Remember, the lower the value how more jumpkeys are generated and
	// how faster jumpkeys are recalculated on insert.

	const USHORT jumpAreaSize = 512 + ((int) sqrt((float) key_length) * 16);

	//  key_size  |  jumpAreaSize
	//  ----------+-----------------
	//         4  |    544
	//         8  |    557
	//        16  |    576
	//        64  |    640
	//       128  |    693
	//       256  |    768

	WIN* window = NULL;
	bool error = false;