dovecot - Dec 2020 - doveadm backup -f -n inbox doing writes?

If I start a 'doveadm backup -f -n inbox' on the source server, why do 
also disk writes increase on the source server (indexes mostly?)

> On 22/12/2020 00:12 Marc Roos <m.roos at f1-outsourcing.eu> wrote:
> 
>  
> If I start a 'doveadm backup -f -n inbox' on the source server, why
do
> also disk writes increase on the source server (indexes mostly?)
Probably because your indexes are not up to date? 

Aki