Re: TODO : Allow parallel cores to be used by vacuumdb [ WIP ]

On Thu, Jun 26, 2014 at 2:35 AM, Dilip kumar <dilip(dot)kumar(at)huawei(dot)com> wrote:

>
> Thank you for giving your time, Please review the updated patch attached in
> the mail.
>
>
>
> 1. Rebased the patch
>
> 2. Implemented parallel execution for new option --analyze-in-stages

Hi Dilip,

Thanks for rebasing.

I haven't done an architectural or code review on it, I just applied
it and used it a little on Linux.

Based on that, I find most importantly that it doesn't seem to
correctly vacuum tables which have upper case letters in the name,
because it does not quote the table names when they need quotes.

Of course that needs to be fixed, but taking it as it is, the
resulting error message to the console is just:

: Execute failed

Which is not very informative. I get the same error if I do a "pg_ctl
shutdown -mi" while running the parallel vacuumdb. Without the -j
option it produces a more descriptive error message "FATAL:
terminating connection due to administrator command", so something
about the new feature suppresses the informative error messages.

I get some compiler warnings with the new patch:

vac_parallel.c: In function 'parallel_msg_master':
vac_parallel.c:147: warning: function might be possible candidate for
'gnu_printf' format attribute
vac_parallel.c:147: warning: function might be possible candidate for
'gnu_printf' format attribute
vac_parallel.c: In function 'exit_horribly':
vac_parallel.c:1071: warning: 'noreturn' function does return

In the usage message, the string has a tab embedded within it
(immediately before "use") that should be converted to literal spaces,
otherwise the output of --help gets misaligned:

printf(_(" -j, --jobs=NUM use this many parallel
jobs to vacuum\n"));

Thanks for the work on this.

Cheers,

Jeff