Re: Bug: Buffer cache is not scan resistant - Mailing list pgsql-hackers

From Grzegorz Jaskiewicz
Subject Re: Bug: Buffer cache is not scan resistant
Date
Msg-id 6A435FB4-81CF-49A2-9001-E8D34581CDE3@pointblue.com.pl
Whole thread Raw
In response to Re: Bug: Buffer cache is not scan resistant  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
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
gj@pointblue.com.pl





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