Re: Progress reporting for pg_verify_checksums

On Tue, Dec 25, 2018 at 07:05:30PM +0100, Fabien COELHO wrote:
> You use 1024² bytes. What about 1000000 bytes per MB, as the unit is about
> stored files?
>
> Also, you did not answer to my other points:
> - use "instr_time.h" for better precision
> - invert sizeonly
> - reuse a test

It seems to me that the SIGUSR1 business is not necessary for the
basic layer of this feature, so I would rather rip that off now. If
necessary we could always discuss that later on. My take about the
option is that --progress should not be the default, but that reports
should only be provided if the caller wants them.

--quiet may have some value by itself, but that seems like a separate
discussion to me.

+ /*
+ * If we are reporting to a terminal, send a carriage return so that we
+ * stay on the same line. If not, send a newline.
+ */
+ if (isatty(fileno(stderr)))
+ fprintf(stderr, "\r");
+ else
+ fprintf(stderr, "\n");
This bit is not really elegant, why not just '\r'?

+ /* The same for total size */
+ if (current_size > total_size)
+ total_size = current_size / 1048576;
Let's use that in a variable and not hardcode the number.

What's introduced here is very similar to what progress_report() does
in pg_rewind/logging.c. The report depends on the context so this
cannot be a common routine logic but perhaps we could keep a
consistent output for both tools?
--
Michael