Re: 9.4 checksum error in recovery with btree index

On Mon, May 19, 2014 at 3:32 AM, Heikki Linnakangas <hlinnakangas(at)vmware(dot)com
> wrote:

> On 05/18/2014 06:30 AM, Jeff Janes wrote:
>
>> On Saturday, May 17, 2014, Heikki Linnakangas <hlinnakangas(at)vmware(dot)com>
>> wrote:
>>
>>>
>>>
>>>> The seems to have fixed it.
>>
>
> Okay, thanks, committed.
>
> Your torn-page generator seems to be very good at finding bugs - any
> chance you could publish it?
>

What would be a good way of doing that? Mostly I've just been sharing it
on google drive when I find something. Should I fork the mirror from
github (https://github.com/postgres/postgres)? Forking the entire codebase
just to have a 200 line patch and 2 driving scripts seems excessive, but I
guess that that is the git philosophy. Or is there a better way than that?

This is a recent one on google drive here:
https://drive.google.com/folderview?id=0Bzqrh1SO9FcESDZVeFk5djJaeHM&usp=sharing

It is the one that I used for testing gin indexes, not the one that was at
issue here.

>
> I wonder if it could've caught the similar mishap in the clearing of the
> incomplete-split flag. I think you'd a checkpoint to begin in the very
> narrow window between splitting a page and inserting the parent pointer.

I could re-introduce that bug and see if it would be found, but I've
already moved on to testing fk (which is what I was trying to test when I
found the btree bug) and I don't think I preserved the original code, so I
don't know how effective it would be as a test. (I guess that speaks in
favor of using git to record the source code as of each interesting point.)

Cheers,

Jeff