Re: RFC: Logging plan of the running query

From: Ashutosh Bapat <ashutosh(dot)bapat(dot)oss(at)gmail(dot)com>
To: Julien Rouhaud <rjuju123(at)gmail(dot)com>
Cc: James Coleman <jtc331(at)gmail(dot)com>, Robert Haas <robertmhaas(at)gmail(dot)com>, Andres Freund <andres(at)anarazel(dot)de>, torikoshia <torikoshia(at)oss(dot)nttdata(dot)com>, pgsql-hackers(at)lists(dot)postgresql(dot)org, Étienne BERSAC <etienne(dot)bersac(at)dalibo(dot)com>, rafaelthca(at)gmail(dot)com, jian(dot)universality(at)gmail(dot)com
Subject: Re: RFC: Logging plan of the running query
Date: 2024-02-26 06:49:42
Message-ID: CAExHW5u6UFMHbZd2KW=Ri=6FedUPD75+rKfzmDr804F6ho9Yig@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Sun, Feb 25, 2024 at 5:00 PM Julien Rouhaud <rjuju123(at)gmail(dot)com> wrote:
>
> On Sat, Feb 24, 2024 at 08:56:41AM -0500, James Coleman wrote:
> > On Fri, Feb 23, 2024 at 10:23 AM Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> > >
> > > On Fri, Feb 23, 2024 at 7:50 PM Julien Rouhaud <rjuju123(at)gmail(dot)com> wrote:
> > > >
> > > > But it doesn't have to be all or nothing right? I mean each call could say
> > > > what the situation is like in their context, like
> > > > CHECK_FOR_INTERRUPTS(GUARANTEE_NO_HEAVYWEIGHT_LOCK | GUARANTEE_WHATEVER), and
> > > > slowly tag calls as needed, similarly to how we add already CFI based on users
> > > > report.

That has some potential ...

>
> Yeah, trying to find a generalized solution seems like worth investing some
> time to avoid having a bunch of CHECK_FOR_XXX() calls scattered in the code a
> few years down the road.
>
> I might be missing something, but since we already have a ton of macro hacks,
> why not get another to allow CFI() overloading rather than modifying every
> single call? Something like that should do the trick (and CFIFlagHandler() is
> just a naive example with a function call to avoid multiple evaluation, should
> be replaced with anything that required more than 10s thinking):
>
> #define CHECK_FOR_INTERRUPTS_0() \
> do { \
> if (INTERRUPTS_PENDING_CONDITION()) \
> ProcessInterrupts(); \
> } while(0)
>
> #define CHECK_FOR_INTERRUPTS_1(f) \
> do { \
> if (INTERRUPTS_PENDING_CONDITION()) \
> ProcessInterrupts(); \
> \
> CFIFlagHandler(f); \
> } while(0)

From your earlier description I thought you are talking about flags
that can be ORed. We need only two macros above. Why are we calling
CFIFLagHandler() after ProcessInterrupts()? Shouldn't we pass flags to
ProcessInterrupts() itself.

>
> #define CHECK_FOR_INTERRUPTS_X(x, f, CFI_IMPL, ...) CFI_IMPL
>
> #define CHECK_FOR_INTERRUPTS(...) \
> CHECK_FOR_INTERRUPTS_X(, ##__VA_ARGS__, \
> CHECK_FOR_INTERRUPTS_1(__VA_ARGS__), \
> CHECK_FOR_INTERRUPTS_0(__VA_ARGS__) \
> )
>
> We would have to duplicate the current CFI body, but it should never really
> change, and we shouldn't end up with more than 2 overloads anyway so I don't
> see it being much of a problem.

Why do we need this complex macro?

--
Best Wishes,
Ashutosh Bapat

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Shlok Kyal 2024-02-26 06:55:42 Re: Add publisher and subscriber to glossary documentation.
Previous Message Masahiko Sawada 2024-02-26 06:46:53 Re: Improve eviction algorithm in ReorderBuffer