Buffer cache is not LRU?!

I was always under the impression that purging of the buffer cache always occurred in a least recently used manner. But then I read in this book, regarding how space in the buffer cache is managed during full table scan operations,

"In this case, Oracle eliminates the buffers almost immediately after reading them into memory in a FIFO (first in, first out) fashion to prevent the buffer cache from being inundated with useless new information and degrading performance"

. Is this true? In what circumstances does Oracle apply LRU when purging the buffer cache?

Thanks, - Dave Received on Fri Apr 09 2004 - 09:03:02 CDT