Re: [PATCH] Prefetch index pages for B-Tree index scans

On Fri, Nov  2, 2012 at 09:59:08AM -0400, John Lumby wrote:
> Thanks for the mentioning this posting.    Interesting.
> However,    the OP describes an implementation based on libaio. 
> Today what we have (for linux) is librt,  which is quite different.
> It is arguable worse than libaio (well actually I am sure it is worse)
> since it is essentially just an encapsulation of using threads to do
> synchronous ios  -  you can look at it as making it easier to do what the 
> application could do itself if it set up its own pthreads.     The linux
> kernel does not know about it and so the CPU overhead of checking for
> completion is higher.

Well, good thing we didn't switch to using libaio, now that it is gone.

-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +