There is one instance of redis in the web view at emoncms/index.php and then instances of redis in each background process. The background processes: feedwriter, phpmqtt_input dont interact with service-runner. If they did interact a sequential switch between prefix contexts should still be fine.
grep -e "new Redis" -rnw emoncms
emoncms/Modules/packetgen/copyto_raspberrpi_module/raspberrypi_run.php:28: $redis = new Redis();
emoncms/index.php:33: $redis = new Redis();
emoncms/scripts/feedwriter.php:26: $redis = new Redis();
emoncms/scripts/export_montly_cron.php:34: $redis = new Redis();
emoncms/scripts/phpmqtt_input.php:77: $redis = new Redis();
emoncms/scripts/input_queue_processor.php:28: $redis = new Redis();