Date: Fri, 12 Apr 2019 13:24:06 -0400
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Peter Geoghegan <pg@bowt.ie>
Cc: Tom Lane <tgl@sss.pgh.pa.us>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Reducing the runtime of the core regression tests
Message-ID: <20190412172406.GA23214@alvherre.pgsql>
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On 2019-Apr-12, Peter Geoghegan wrote:

> On Fri, Apr 12, 2019 at 9:31 AM Alvaro Herrera <alvherre@2ndquadrant.com> wrote:
> > Done.  Do you have a preferred spot where the counts were wrong?
> 
> Not really, but I can give you an example.
> 
> Line counts for each of the two "break" statements within
> _bt_keep_natts_fast() are exactly the same. I don't think that this
> because we actually hit each break exactly the same number of times
> (90,236 times). I think that we see this because the same instruction
> is associated with both break statements in the loop. All of the
> examples I've noticed are a bit like that. Not a huge problem, but
> less useful than the alternative.

Hmm, it's odd, because
https://coverage.postgresql.org/src/backend/access/nbtree/nbtutils.c.gcov.html
still shows that function doing that.  pg_config shows:

$ ./pg_config --configure
'--enable-depend' '--enable-coverage' '--enable-tap-tests' '--enable-nls' '--with-python' '--with-perl' '--with-tcl' '--with-openssl' '--with-libxml' '--with-ldap' '--with-pam' 'CFLAGS=-O0'

src/Makefile.global says:

CFLAGS = -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Werror=vla -Wendif-labels -Wmissing-format-attribute -Wformat-security -fno-strict-aliasing -fwrapv -fexcess-precision=standard -fprofile-arcs -ftest-coverage -O0

the compile line for nbtutils is:

gcc -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Werror=vla -Wendif-labels -Wmissing-format-attribute -Wformat-security -fno-strict-aliasing -fwrapv -fexcess-precision=standard -fprofile-arcs -ftest-coverage -O0 -I../../../../src/include  -D_GNU_SOURCE -I/usr/include/libxml2   -c -o nbtutils.o nbtutils.c -MMD -MP -MF .deps/nbtutils.Po

so I suppose there's something else that's affecting this.

I wonder if it would be useful to add --enable-debug.  I think I
purposefully removed that, but I don't remember any details about it.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services