VDS - is httpd behavior normal?

Question

Nginx

The question is more general. Everything works, but here is the resource consumption that takes place - can it be reduced?
Introductory :
There is a VDS from hetzner.de (1GB of memory, 1 core 2.4GHz), a static file share is spinning on it (gives nginx over http), several wp-blogs (attendance ~ 100 uniques per day), a couple of business card sites (php without bd).
centos 7 , nginx - front-end, apache2 - back-end, mariadb - typical lamp.
nginx returns all the statics, one of the sites uses ssl, the main load (judging by the logs) is taken by the fileshare (~25k requests per day). (the last hours on the graph are some experiments related to httpd) Key points of the httpd config:

<IfModule mpm_prefork_module>
  # Число процессов, запускаемых вначале
  StartServers 2
  # Мин. и макс. число ожидаемых процессов
  MinSpareServers 1
  MaxSpareServers 4
  # Максимальное число параллельных запросов
  MaxClients 8
  # Число запросов, обрабатываемых за дочерний процесс/поток
  MaxRequestsPerChild 1024
</IfModule>

Key points of mariadb config:

[mysqld]
key_buffer = 16M
max_allowed_packet = 4M
table_cache = 32
sort_buffer_size = 2M
read_buffer_size = 4M
read_rnd_buffer_size = 2M
net_buffer_length = 20K
thread_stack = 640K
tmp_table_size = 16M
query_cache_limit = 2M
query_cache_size = 16M
max_connections = 64
max_user_connections = 8
max_delayed_threads = 6
skip-networking
skip-federated
skip-blackhole
skip-archive
skip-external-locking

Actually, the question is:
Is it normal that httpd and mariadb take on average ~ 90mb each? Once a day, log rotation is triggered, which restarts the demons, but this is not a solution to a possible problem

Answer 1

You can probably save something on apache and mysql, but why? If there are no problems then why optimize?
PS How is the graph drawn?