On Sat, Aug 06, 2016 at 03:54:56PM +0300, Alexey Dobriyan wrote:
[sprintf sucks, let's convert numbers manually]
> --- a/mm/vmstat.c
> +++ b/mm/vmstat.c
> @@ -1592,7 +1592,10 @@ static int vmstat_show(struct seq_file *m, void *arg)
> {
> unsigned long *l = arg;
> unsigned long off = l - (unsigned long *)m->private;
> - seq_printf(m, "%s %lu\n", vmstat_text[off], *l);
> +
> + seq_puts(m, vmstat_text[off]);
> + seq_put_decimal_ull(m, ' ', *l);
> + seq_putc(m, '\n');
> return 0;
> }
If that manages to be a hotspot, we really should
* educate the wankers responsible for the userland code in question,
until they repent and cease committing such abominations.
* look into fixing vsnprintf().
Seriously, what the hell is vsnprintf() doing that takes so much time? It's
not as if it was a complex format anyway. WTF is going on there? Where is
it spending that much time?
