Re: proposal: Set effective_cache_size to greater of .conf value, shared_buffers

On Thu, May 15, 2014 at 10:23:19PM +0900, Amit Langote wrote:
> On Thu, May 15, 2014 at 9:06 PM, Bruce Momjian <bruce@momjian.us> wrote:
> >
> > This is the same problem we had with auto-tuning work_mem, in that we
> > didn't know what other concurrent activity was happening.  Seems we need
> > concurrent activity detection before auto-tuning work_mem and
> > effective_cache_size.
> >
> 
> Perhaps I am missing something obvious here, but would mmgr have any
> useful numbers on this? Like any book-keeping info maintained by
> mcxt.c/aset.c? Would extending that interface help?

No, all memory allocat is per-process, except for shared memory.  We
probably need a way to record our large local memory allocations in
PGPROC that other backends can see;  same for effective cache size
assumptions we make.

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