@Override
    public MeterIdPrefix activeRequestPrefix(MeterRegistry registry, RequestOnlyLog log) {
        /* hostname.pattern, method, service */
        final Builder<Tag> tagListBuilder = ImmutableList.builderWithExpectedSize(3);
        addActiveRequestPrefixTags(tagListBuilder, log);
        return new MeterIdPrefix(name, tagListBuilder.build());
    }
Returns a newly created {@link GrpcMeterIdPrefixFunction} with the specified {@code name}.
grpc/src/main/java/com/linecorp/armeria/common/grpc/GrpcMeterIdPrefixFunction.java