Michael Paquier <michael.paquier@gmail.com> writes:
> On Wed, Jul 19, 2017 at 8:56 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> I wonder if it'd be worth the trouble to stick something like this into
>> xlog.c:
>> StaticAssertStmt(sizeof(ControlFileData) <= 512,
>> "pg_control is too large for atomic disk writes");
> +1. Even if it just gets triggered in 20 years by some hacker, that's
> a good reminder about assumptions behind the update logic.
Done. I found the size checks had metastasized into pg_resetwal as well,
and probably should have been in pg_rewind since it also rewrites
pg_control, so it ended up a slightly larger patch than I first thought.
Seems cleaner than before though.
regards, tom lane