Dashboard add all values while querying Prometheus

I have 10 variables on my dashboard and all variables have “All” as Dropdown. when first time dashboard loads , it appends all values of each variable to query.

$instance = 1000 values
$prism_target_host = 1000 values

since we have so many IP address (100+) query takes a while. how i can optimize query?
is there way to define space value in option? i tried but it takes All as default


max by (instance,prism_target_host)(rate(prism_jedis_sync_retries{Environment =~’$Environment’,Region =~’$Region’,prism_side =~’$prism_side’,prism_cluster =~’$prism_cluster’,prism_target_zone =~’$prism_target_zone’,prism_target_host =~’$prism_target_host’,prism_target_ip =~’$prism_target_ip’,handler_name =~’$handler_name’,handler_class =~’$handler_class’,AvailabilityZone =~’$AvailabilityZone’,instance =~’$instance’}[5m]))