I'm going to use the PubSubClient lib to subscribe to a fairly large amount of topics (say ~1000). The topics will be stored on a CSV file on an SD card, and read in the setup. So I'd like not to hard code them.
That got me thinking, how much RAM would does subscribing to a topic use.
The library does mention a 256 byte buffer, but not sure if this is per topic, or per server.
I did try looking into the pubsubclient::subscribe code, but it goes a bit over my head.
Any help is appriciated.