Re: TAP test breakage on MacOS X

On Thu, Oct 30, 2014 at 10:49:33PM -0400, Tom Lane wrote:
> Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
> > There are other issues. I am not going to enable this in the buildfarm
> > until the check test can work from a single install. It's insane for the
> > bin tests to take an order of magnitude longer than the main regression
> > suite.
>
> I think the installs as such aren't the only reason for the sucky
> performance. We need to also reduce the number of initdb cycles incurred
> by the TAP tests. It's useless for example that the pg_controldata test
> creates its very own $PGDATA rather than sharing one with other tests.
>
> This line of thought implies that the tests will become less independent
> of each other, which will probably result in them being a bit harder to
> maintain. Still, we are paying an awful lot of cycles for not much, as
> things stand at the moment.

One could memoize initdb within the suite. Call it once per distinct command
line, caching the resulting data directory. Copy the cached data directory
for each test desiring one.