[rt-users] RT 4.4.1 and transaction isolation level on Postgres

[Václav Ovsík]

On Wed, Jan 04, 2017 at 04:50:11AM -0800, Alex Vandiver wrote:
>... 
> MySQL suffers from the exact same problem -- but, as it happens,
> both more silently and more catastrophically.  See
> https://github.com/bestpractical/rt/commit/e36364c5

Eh. I'm glad I did transition from Mysql to Postgres years ago :).

> > I can change isolation level in postgresql.conf to 'repeatable read'
> > and things are different.
> 
> I advise against doing that.  Upon inspection, RT is not prepared to
> deal with the "could not serialize access due to concurrent update"
> errors that arise from updates to rows in multiple transactions in
> Postgres' repeatable-read isolation.

OK, thanks!

> Repeatable-read is only possible in MySQL because it has a fascinating
> definition of "repeatable":
> ...
> > Should I change the default isolation level on Postgres for RT to
> > 'repeatable read'?
> 
> No.  You should try the 4.4/previewscrips-race branch, which I've just
> pushed:
> 
> https://github.com/bestpractical/rt/compare/4.4-trunk...4.4/previewscrips-race
> 
> The gory details are contained in the commits therein.

You have my respect! Wonderful job. I tried your changes on my test
instance first. The problem is solved I think.
I installed changes to production instance too.
Thanks for your time and effort!
-- 
Zito