On Mar 5, 2007, at 2:36 AM, Tom Lane wrote:
n into account.

I'm also less than convinced that it'd be helpful for a big seqscan:
won't reading a new disk page into memory via DMA cause that memory to
get flushed from the processor cache anyway?

Nope. DMA is writing directly into main memory. If the area was in the L2/L1 cache, it will get invalidated. But if it isn't there, it is okay.

Grzegorz Jaskiewicz

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