Re: [COMMITTERS] pgsql: Improved parallel make support

I tried another experiment, which was "make -j100 all" on my relatively
new Linux box (2 dual-core CPUs).  It blew up real good, as per attached
stderr output, which shows evidence of more missing dependencies as well
as some additional cases of concurrent attempts to build the same
target.

It's clear to me that we are very far from having a handle on what it'll
really take to run parallel builds safely, and I am therefore now of the
opinion that we ought to revert the patch.  Hypothetical gains in
parallelism are useless if we can't actually use parallel building
reliably.  We are currently worse off than before in terms of time to
build the system.
        regards, tom lane

/usr/bin/ld: cannot find -lpgport
collect2: ld returned 1 exit status
make[3]: *** [refint.so] Error 1
make[2]: *** [../../../contrib/spi/refint.so] Error 2
make[2]: *** Waiting for unfinished jobs....
path.c: In function 'get_html_path':
path.c:615: error: 'HTMLDIR' undeclared (first use in this function)
path.c:615: error: (Each undeclared identifier is reported only once
path.c:615: error: for each function it appears in.)
path.c: In function 'get_man_path':
path.c:624: error: 'MANDIR' undeclared (first use in this function)
make[3]: *** [path.o] Error 1
make[3]: *** Deleting file `path.o'
make[3]: *** Waiting for unfinished jobs....
/usr/bin/ld: cannot find -lpgport
collect2: ld returned 1 exit status
make[3]: *** [autoinc.so] Error 1
make[2]: *** [../../../contrib/spi/autoinc.so] Error 2
make[2]: *** [submake-libpgport] Error 2
make[2]: *** Waiting for unfinished jobs....
ln: creating symbolic link `libpgtypes.so.3': File exists
make[4]: *** [libpgtypes.so.3.2] Error 1
make[4]: *** Deleting file `libpgtypes.so.3.2'
make[3]: *** [all-pgtypeslib-recurse] Error 2
make[3]: *** Waiting for unfinished jobs....
make[1]: *** [all-test/regress-recurse] Error 2
make[1]: *** Waiting for unfinished jobs....
In file included from gram.y:12102:
scan.c: In function 'yy_try_NUL_trans':
scan.c:16246: warning: unused variable 'yyg'
ln: creating symbolic link `libpq.so.5': File exists
make[4]: *** [libpq.so.5.4] Error 1
make[4]: *** Deleting file `libpq.so.5.4'
make[3]: *** [submake-libpq] Error 2
make[2]: *** [all-pg_dump-recurse] Error 2
make[2]: *** Waiting for unfinished jobs....
ln: creating symbolic link `libpq.so.5': File exists
make[6]: *** [libpq.so.5.4] Error 1
make[6]: *** Deleting file `libpq.so.5.4'
make[5]: *** [submake-libpq] Error 2
make[4]: *** [submake-ecpglib] Error 2
make[3]: *** [all-compatlib-recurse] Error 2
/usr/bin/ld: cannot open linker script file ../../../src/interfaces/libpq/libpq.so: No such file or directory
collect2: ld returned 1 exit status
make[3]: *** [psql] Error 1
make[2]: *** [all-psql-recurse] Error 2
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_reset_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1426: undefined reference to `pthread_sigmask'
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_block_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1363: undefined reference to `pthread_sigmask'
collect2: ld returned 1 exit status
make[3]: *** [createdb] Error 1
make[3]: *** Waiting for unfinished jobs....
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_reset_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1426: undefined reference to `pthread_sigmask'
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_block_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1363: undefined reference to `pthread_sigmask'
collect2: ld returned 1 exit status
make[3]: *** [createuser] Error 1
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_reset_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1426: undefined reference to `pthread_sigmask'
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_block_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1363: undefined reference to `pthread_sigmask'
collect2: ld returned 1 exit status
make[3]: *** [dropuser] Error 1
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_reset_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1426: undefined reference to `pthread_sigmask'
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_block_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1363: undefined reference to `pthread_sigmask'
collect2: ld returned 1 exit status
make[3]: *** [vacuumdb] Error 1
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_reset_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1426: undefined reference to `pthread_sigmask'
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_block_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1363: undefined reference to `pthread_sigmask'
collect2: ld returned 1 exit status
make[3]: *** [dropdb] Error 1
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_reset_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1426: undefined reference to `pthread_sigmask'
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_block_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1363: undefined reference to `pthread_sigmask'
collect2: ld returned 1 exit status
make[3]: *** [clusterdb] Error 1
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_reset_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1426: undefined reference to `pthread_sigmask'
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_block_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1363: undefined reference to `pthread_sigmask'
collect2: ld returned 1 exit status
make[3]: *** [reindexdb] Error 1
make[2]: *** [all-scripts-recurse] Error 2
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_reset_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1426: undefined reference to `pthread_sigmask'
../../../src/interfaces/libpq/libpq.a(fe-secure.o): In function `pq_block_sigpipe':
/home/tgl/pgsql/src/interfaces/libpq/fe-secure.c:1363: undefined reference to `pthread_sigmask'
collect2: ld returned 1 exit status
make[3]: *** [pg_ctl] Error 1
make[2]: *** [all-pg_ctl-recurse] Error 2
make[1]: *** [all-bin-recurse] Error 2
make[2]: *** [all-ecpg-recurse] Error 2
make[1]: *** [all-interfaces-recurse] Error 2
make[1]: *** [all-backend-recurse] Error 2
make: *** [all-src-recurse] Error 2