Last and sum in Kibana ESSQL

[xquest (Pat)]

Hi!
I am using Kiban canvas and sometimes Kibana canvas expression editor.

I got some search:

SELECT host.name as n, system.diskio.name as s,
last(system.diskio.io.time,"@timestamp") as v
FROM "<metricbeat-7.11.1-{now/d}>"
where n is not null and s is not null
group by n, s
order by v desc

and in result I got:

serv1     sda     120
serv1     sdg     400
serv1     spf      300
serv5     sda     200

How to modify this search to sum this value, but only last value sum(last) doesn't work.

I want to get result like:

serv1        820
serv5        200

Is it possible in Kibana sql or Kibana essql?