when haproxy is built with libslz (not zlib), the following metrics are irrelevant
# HELP haproxy_process_current_zlib_memory Amount of memory currently used by HTTP compression on the current worker process (in bytes)
# TYPE haproxy_process_current_zlib_memory gauge
haproxy_process_current_zlib_memory NaN
# HELP haproxy_process_max_zlib_memory Limit on the amount of memory used by HTTP compression above which it is automatically disabled (in bytes, see global.maxzlibmem)
# TYPE haproxy_process_max_zlib_memory gauge
haproxy_process_max_zlib_memory NaN
we need not to add that metric if haproxy is built with slz
when haproxy is built with libslz (not zlib), the following metrics are irrelevant
we need not to add that metric if haproxy is built with slz