gather - best way to issue parallel commands?

[eoghanmurray]

I wanted to add up (read) a bunch of sorted sets in as short as possible time window so that I could write an estimated total and minimize the time window where the sets could be modified:

approx_total = sum(await asyncio.gather(
                *map(cx.zcard, list_of_keys)))
await cx.set('zcards-approx-total', approx_total)

This didn't work as it hit a 'Too many connections' error. As this is on RedisCluster, there is a Connection Pool in effect with a limit of 32.

I'm asking this as it struck me that aredis could provide a built in gather function to do this in a max_connections-aware manner.
Is that something that is feasible? or desirable?