You can use the "nice" value of a process to decrease its execution priority in Linux, so that way you can tell your app to be more polite.
Just a mathematical example:
If you have a total workload of 1200 CPU units needed for your startup, and
- instead of doing 6 secs of a load 200 units/s that would max out you CPU,
- you do 15 seconds of a load of 80, which leaves lots of CPU free for other tasks during those 15 seconds.
So, your startup will take 15 seconds instead of 6. And the max momentary CPU utilisation would be 80 instead of 200, meaning that 120 units would be free for other tasks during the startup.
Note that the nice value in procd means the value for the whole process lifetime. Not just for startup.
- https://en.wikipedia.org/wiki/Nice_(Unix)
- https://www.tecmint.com/set-linux-process-priority-using-nice-and-renice-commands/
And as an answer to your question in How to Change Process Priority? - #3 by davidgates , the default nice value is 0.
"niceness" ranges from -20 (highest priority value) to 19 (lowest priority value).
Note below in my example (taken with "htop" app) from "NI" column that
- most apps have the default 0
- the NTP daemon is priority hungry with niceness of -15
- the statistics collection apps are more polite with nlbwmon with 19 and collectd with 5
root@router1:~# htop
0[|| 1.3%] Tasks: 23, 10 thr; 1 running
1[| 0.7%] Load average: 0.00 0.00 0.00
Mem[|||||||||||||||| 98.8M/465M] Uptime: 3 days, 18:29:03
Swp[ 0K/0K]
PID USER PRI NI VIRT RES SHR S CPU% MEM% TIME+ Command
19076 root 20 0 1756 1548 872 R 1.3 0.3 0:00.13 htop
1 root 20 0 1400 860 680 S 0.0 0.2 0:15.16 /sbin/procd
301 ubus 20 0 1052 692 596 S 0.0 0.1 0:03.00 /sbin/ubusd
302 root 20 0 704 512 476 S 0.0 0.1 0:00.03 /sbin/askfirst /usr/libexec/login.sh
336 root 20 0 816 568 524 S 0.0 0.1 2:15.61 /sbin/urngd
1013 logd 20 0 1152 788 540 S 0.0 0.2 0:00.39 /sbin/logd -S 128
1065 root 20 0 2004 1140 836 S 0.0 0.2 0:01.24 /sbin/rpcd -s /var/run/ubus/ubus.sock -t 30
1330 root 20 0 888 700 660 S 0.0 0.1 0:00.01 /usr/sbin/dropbear -F -P /var/run/dropbear.1.pid -p 22 -K 3
1449 root 20 0 4484 2796 2500 S 0.0 0.6 22:04.29 /usr/sbin/hostapd -s -g /var/run/hostapd/global
1450 root 20 0 4388 1884 1684 S 0.0 0.4 0:05.63 /usr/sbin/wpa_supplicant -n -s -g /var/run/wpa_supplicant/g
1555 root 20 0 1572 932 788 S 0.0 0.2 1:24.78 /sbin/netifd
1832 root 20 0 1108 764 728 S 0.0 0.2 0:00.22 udhcpc -p /var/run/udhcpc-eth0.2.pid -s /lib/netifd/dhcp.sc
1838 root 20 0 844 604 552 S 0.0 0.1 0:01.06 odhcp6c -s /lib/netifd/dhcpv6.script -P0 -t120 eth0.2
1975 root 20 0 1260 788 660 S 0.0 0.2 1:18.43 /usr/sbin/odhcpd
2490 root 20 0 4272 3516 2704 S 0.0 0.7 0:01.07 /usr/sbin/uhttpd -f -h /www -r router1 -x /cgi-bin -u /ubus
4248 root 5 -15 1112 708 668 S 0.0 0.1 0:00.45 /usr/sbin/ntpd -n -N -S /usr/sbin/ntpd-hotplug -p 0.openwrt
4629 root 39 19 1408 768 652 S 0.0 0.2 7:02.45 /usr/sbin/nlbwmon -o /var/lib/nlbwmon -b 524288 -i 24h -r 3
5756 dnsmasq 20 0 7840 7476 740 S 0.0 1.6 30:20.17 /usr/sbin/dnsmasq -C /var/etc/dnsmasq.conf.cfg01411c -k -x
8231 root 25 5 5996 2376 1500 S 0.0 0.5 1:10.48 /usr/sbin/collectd -C /tmp/collectd.conf -f
8244 root 25 5 5996 2376 1500 S 0.0 0.5 0:00.76 /usr/sbin/collectd -C /tmp/collectd.conf -f
8245 root 25 5 5996 2376 1500 S 0.0 0.5 0:22.07 /usr/sbin/collectd -C /tmp/collectd.conf -f
8246 root 25 5 5996 2376 1500 S 0.0 0.5 0:01.99 /usr/sbin/collectd -C /tmp/collectd.conf -f
8247 root 25 5 5996 2376 1500 S 0.0 0.5 0:02.01 /usr/sbin/collectd -C /tmp/collectd.conf -f
19063 root 20 0 912 664 608 S 0.0 0.1 0:00.11 /usr/sbin/dropbear -F -P /var/run/dropbear.1.pid -p 22 -K 3
19064 root 20 0 1116 904 856 S 0.0 0.2 0:00.01 -ash