Re: [HACKERS] Remove secondary checkpoint - Mailing list pgsql-hackers

From Simon Riggs
Subject Re: [HACKERS] Remove secondary checkpoint
Date
Msg-id CANP8+jK9jkosKQS44gvf2pfaBxOc5Ef_ea3OT0=XDrcg-e20eQ@mail.gmail.com
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In response to Re: [HACKERS] Remove secondary checkpoint  (Simon Riggs <simon@2ndquadrant.com>)
Responses Re: [HACKERS] Remove secondary checkpoint
List pgsql-hackers
On 30 October 2017 at 15:22, Simon Riggs <simon@2ndquadrant.com> wrote:

>> You forgot to update this formula in xlog.c:
>>     distance = (2.0 + CheckPointCompletionTarget) * CheckPointDistanceEstimate;
>>     /* add 10% for good measure. */
>>     distance *= 1.10;
>> You can guess easily where the mistake is.
>
> Doh - fixed that before posting, so I must have sent the wrong patch.
>
> It's the 10%, right? ;-)

So, there are 2 locations that mention 2.0 in xlog.c

I had already fixed one, which is why I remembered editing it.

The other one you mention has a detailed comment above it explaining
why it should be 2.0 rather than 1.0, so I left it.

Let me know if you still think it should be removed? I can see the
argument both ways.

Or maybe we need another patch to account for manual checkpoints.

-- 
Simon Riggs                http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services


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