Re: Vacuum Delay feature - Mailing list pgsql-hackers

From Christopher Browne
Subject Re: Vacuum Delay feature
Date
Msg-id m33c9f6256.fsf@wolfe.cbbrowne.com
Whole thread Raw
In response to Re: Vacuum Delay feature  (Jan Wieck <JanWieck@Yahoo.com>)
List pgsql-hackers
Centuries ago, Nostradamus foresaw when pgman@candle.pha.pa.us (Bruce Momjian) would write:
> I guess my question is that now that we have the new cache
> replacement policy, is the vacuum delay worth while.  I looked at
> http://developer.postgresql.org/~wieck/vacuum_cost/ and does seem
> useful.

They satisfy quite separate use cases, so both are surely useful.

- The new cache replacement policy allows us to make sure that cache isn't getting blown on worthless things.

- Vacuum delay allows us to make sure that we aren't spending all our I/O on vacuuming.

There is overlap between their uses, as both should help diminish the
use of I/O to fill buffers with data that was discarded, but they
surely have separate uses.
-- 
"cbbrowne","@","acm.org"
http://www.ntlug.org/~cbbrowne/lisp.html
You  know  that  little  indestructible  black box  that  is  used  on
planes---why  can't  they  make  the  whole  plane  out  of  the  same
substance?


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