Avoid overhead with fprintf related functions - Mailing list pgsql-hackers

From Ranier Vilela
Subject Avoid overhead with fprintf related functions
Date
Msg-id CAEudQAoXozYNsx3T-PZFk-QraRKYHRRarOhF4C2GuTfrct3g_A@mail.gmail.com
Whole thread Raw
Responses Re: Avoid overhead with fprintf related functions
Re: Avoid overhead with fprintf related functions
List pgsql-hackers
Based on work in [1].
According to https://cplusplus.com/reference/cstdio/fprintf/
The use of fprintf is related to the need to generate a string based on a format, which should be different from "%s".
Since fprintf has overhead when parsing the "format" parameter, plus all the trouble of checking the va_arg parameters.
I think this is one of the low fruits available and easy to reap.
By replacing fprintf with its equivalents, fputs and fputc,
we avoid overhead and increase security [2] and [3].

The downside is a huge big churm, which unfortunately will occur.
But, IHMO, I think the advantages are worth it.
Note that behavior remains the same, since fputs and fputc do not change the expected behavior of fprintf.

A small performance gain is expected, mainly for the client, since there are several occurrences in some critical places, such as (usr/src/fe_utils/print.c).

Patch attached.
This pass check-world.

regards,
Ranier Vilela

Attachment

pgsql-hackers by date:

Previous
From: Melih Mutlu
Date:
Subject: Re: Summary function for pg_buffercache
Next
From: Robert Haas
Date:
Subject: Re: why can't a table be part of the same publication as its schema