Re: Redesigning checkpoint_segments

>>> Default of 4 for min_wal_size?
>>
>> I assume you mean 4 segments; why not 3 as currently?  As long as the
>> system has the latitude to ratchet it up when needed, there seems to
>> be little advantage to raising the minimum.  Of course I guess there
>> must be some advantage or Heikki wouldn't have made it configurable,
>> but I'd err on the side of keeping this one small.  Hopefully the
>> system that automatically adjusts this is really smart, and a large
>> min_wal_size is superfluous for most people.
>
> Keep in mind that the current is actually 7, not three (3*2+1).  So 3
> would be a siginficant decrease.  However, I don't feel strongly about
> it either way.  I think that there is probably a minimum reasonable
> value > 1, but I'm not sure what it is.

Good point.  OK, 4 works for me.

-- 
Robert Haas
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