I'm going to remove subj...
buf_internals.h:
/* * I padded this structure to a power of 2 (PADDED_SBUFDESC_SIZE) * because BufferDescriptorGetBuffer is
calleda billion times and it * does an C pointer subtraction (i.e., "x - y" -> array index of x * relative to y,
whichis calculated using division by struct size).
^^^^^^^^^^^^^^^^^^^^^^^^ * Integer ".div" hits you for 35 cycles, as opposed to a 1-cycle * "sra" ... this hack
cut10% off of the time to create the Wisconsin * database! It eats up more shared memory, of course, but we're *
(allegedly)going to make some of these types bigger soon anyway... * -pma 1/2/93 */
This is not true now:
#define BufferDescriptorGetBuffer(bdesc) ((bdesc)->buf_id + 1)
Comments ?...
Vadim
