Re: Streaming basebackups vs pg_stat_tmp

On Fri, Oct 28, 2016 at 2:44 PM, David Steele <david(at)pgmasters(dot)net> wrote:

> On 10/28/16 11:53 AM, Magnus Hagander wrote:
>
>> In 9.6 and earlier, if you change pg_stat_tmp to be a symlink,
>> basebackups no longer work. That's because we create symlink entry in
>> the tarfile for it instead of an empty directory, but with no data,
>> which Breaks Everything (TM).
>>
>> This was fixed in head in 6ad8ac60, which introduced "more excludes",
>> due to the refactoring. That commit message refers to it also fixing
>> this bug, but it seems the bugfix was never backpatched.
>>
>> Or did I miss something?
>>
>
> I don't think so. I guess it got lost in the CF rush and also slipped my
> mind when I reviewed the final commit.
>
> Attached patch fixds this (based on 9.5 which is where I ran into it,
>> but it needs to go in other back branches as well) by bringing back a
>> (modified) version of the functoin _tarWriteDir() to the back branches.
>>
>> I'd appreciate a look-over before committing, but it works fine in my
>> tests.
>>
>
> The patch looks sane to me, but I think it would be good to backpatch the
> TAP test from the exclusion patch that tests pg_replslot as a symlink.

So that's the test that's in that same patch, 6ad8ac60, right? How much of
the code for that is actually needed? (like the row which changes a 10 to a
11? which probably means something, but is it relevant here?) Or all of it?

--
Magnus Hagander
Me: http://www.hagander.net/
Work: http://www.redpill-linpro.com/