Prometheus how to handle counters on server

Question

I have articles and for each article I want to have read count

# TYPE news_read_counter2 Counter
news_read_counter2{id="2000"} 168

now the counters on the servers are saved in redis\memcached so they can get reset from time to time so after a while the redis machine is restart and the server dont have the last news_read_counter number and if I start from zero again

# TYPE news_read_counter2 Counter
news_read_counter2{id="2000"} 2

now looking at the news_read_counter2{id="2000"} graph I see that the counter is getting dropped to 2 while the docs says:

A counter is a cumulative metric that represents a single numerical value that only ever goes up.

so now to keep track of the news_read_counter I need to save the data into db and I back to the start zone where I need to use mysql to handle my data

here an Image of counter after redis got restart:

Answer 1

Counters are allowed to be reset to 0, so there's no need to do anything special here to handle it. See http://www.robustperception.io/how-does-a-prometheus-counter-work/ for more detail.

It's recommended to use a client library which will handle all of this for you.

Also, by convention you should suffix counters with _total so that metric should be news_reads_total.