RE: speed up a logical replica setup

Dear Vignesh,

I forgot to reply one of the suggestion.

> 2) There is a CheckDataVersion function which does exactly this, will
> we be able to use this:
> +       /* Check standby server version */
> +       if ((ver_fd = fopen(versionfile, "r")) == NULL)
> +               pg_fatal("could not open file \"%s\" for reading: %m",
> versionfile);
> +
> +       /* Version number has to be the first line read */
> +       if (!fgets(rawline, sizeof(rawline), ver_fd))
> +       {
> +               if (!ferror(ver_fd))
> +                       pg_fatal("unexpected empty file \"%s\"", versionfile);
> +               else
> +                       pg_fatal("could not read file \"%s\": %m", versionfile);
> +       }
> +
> +       /* Strip trailing newline and carriage return */
> +       (void) pg_strip_crlf(rawline);
> +
> +       if (strcmp(rawline, PG_MAJORVERSION) != 0)
> +       {
> +               pg_log_error("standby server is of wrong version");
> +               pg_log_error_detail("File \"%s\" contains \"%s\",
> which is not compatible with this program's version \"%s\".",
> +                                                       versionfile,
> rawline, PG_MAJORVERSION);
> +               exit(1);
> +       }
> +
> +       fclose(ver_fd);


This suggestion has been rejected because I was not sure the location of the
declaration and the implementation. Function which could be called from clients
must be declared in src/include/{common|fe_utils|utils} directory. I saw files
located at there but I could not appropriate location for CheckDataVersion.
Also, I did not think new file should be created only for this function.

Best Regards,
Hayato Kuroda
FUJITSU LIMITED
https://www.fujitsu.com/