Re: [Qemu-devel] [RFC] virtio: Report new guest memory statistics pertinent to memory ballooning (V2)

[Jamie Lokier]

Adam Litke wrote:
> +static inline void print_stat(Monitor *mon, uint32_t val, const char *label)
> +{
> +    if (val != -1) {
> +        monitor_printf(mon, ",%s=%u", label, val);
> +    }
> +}
> +
>  static void do_info_balloon(Monitor *mon)
>  {
> -    ram_addr_t actual;
> +    QEMUBalloonState s;
> +    int ret;
>  
> -    actual = qemu_balloon_status();
> -    if (kvm_enabled() && !kvm_has_sync_mmu())
> +    ret = qemu_balloon_status(&s);
> +    if (kvm_enabled() && !kvm_has_sync_mmu()) {
>          monitor_printf(mon, "Using KVM without synchronous MMU, "
>                         "ballooning disabled\n");
> -    else if (actual == 0)
> +    } else if (ret < 0) {
>          monitor_printf(mon, "Ballooning not activated in VM\n");
> -    else
> -        monitor_printf(mon, "balloon: actual=%d\n", (int)(actual >> 20));
> +    } else {
> +        monitor_printf(mon, "balloon: actual=%d", (int)(s.actual >> 20));
> +        print_stat(mon, s.stats.pswapin, "pages_swapped_in");
> +        print_stat(mon, s.stats.pswapout, "pages_swapped_out");
> +        print_stat(mon, s.stats.panon, "anon_pages");
> +        print_stat(mon, s.stats.pgmajfault, "major_page_faults");
> +        print_stat(mon, s.stats.pgminfault, "minor_page_faults");
> +        print_stat(mon, s.stats.memfree, "free_memory");
> +        print_stat(mon, s.stats.memtot, "total_memory");
> +        monitor_printf(mon, "\n");
> +    }
> +        
>  }

These days, would it make more sense to emit a QJSON object?

In this case the JSON object is quite human readable too.

-- Jamie