Heikki Linnakangas <heikki@enterprisedb.com> writes:
> Tom Lane wrote:
>> I tend to agree with whoever said upthread that the combination of GUC
>> variables proposed here is confusing and ugly. It'd make more sense to
>> have min and max checkpoint rates in KB/s, with the max checkpoint rate
>> only honored when we are predicting we'll finish before the next
>> checkpoint time.
> Really? I thought everyone is happy with the current combination, and
> that it was just the old trio of parameters controlling the write, nap
> and sync phases that was ugly. One particularly nice thing about
> defining the duration as a fraction of checkpoint interval is that we
> can come up with a reasonable default value that doesn't depend on your
> hardware.
That argument would hold some water if you weren't introducing a
hardware-dependent min rate in the same patch. Do we need the min rate
at all? If so, why can't it be in the same units as the max (ie, a
fraction of checkpoint)?
> How would a min and max rate work?
Pretty much the same as the code does now, no? You either delay, or not.
regards, tom lane
