Log metrics on network I/O with minimal resource use
This fleet (netio-logger) logs network I/O metrics on a configurable interval. It is designed to be a drop-in replacement for Network Metrics Logger (NML) with much reduced resource requirements to support testing with a user's application containers. Like NML, netio-logger generates minimal output to avoid creation of more network I/O itself.
| Fleet | Resident Memory | Disk | Containers |
|---|---|---|---|
| NML | 224 MB | 320 MB | 3 |
| netio-logger | 39 MB | 36 MB | 1 |
Resident memory includes approximately 38 MB per container for the balena-containerd-shim process. The netio-logger executable itself uses 1 MB of resident memory and the executable size is 256 KB.
To be fair, NML emphasizes composability from a generic system metrics container and a separate logging container. The idea with netio-logger is to give users a choice depending on their needs.
Simply click on the Deploy with balena button below to create a fleet from the docker-compose file in this repository. Alternatively, you can copy the directives for the netio-logger service into your own docker-compose.
By default the fleet publishes bytes transmitted and received every five minutes on the loopback interface lo. Output is formatted as CSV. You should see messages like below.
11.07.22 12:54:36 (+0000) netio-logger Received initial loggable message for interface lo; starting publish interval
11.07.22 12:59:36 (+0000) netio-logger elapsedRx,elapsedTx
11.07.22 12:59:36 (+0000) netio-logger 40976,40976
11.07.22 13:04:36 (+0000) netio-logger 42868,42868
Notice the first message includes the name of the interface. See METRICS_REQUEST configuration below to specify a different interface.
Environment variables you may configure are listed in the sections below.
The METRICS_REQUEST variable defines the network interface of interest, and defaults to the loopback interface, lo. For example, if you are interested in interface eth0, set METRICS_REQUEST like below.
networkStats/(eth0)
If you don't know the name of the interface, use the ifconfig command to find it. The example below includes an Ethernet interface, eth0, and a cellular interface, wwp1s0u1u1i4.
Click for ifconfig command example
root@abcdef0:~# ifconfig |grep -B 1 inet
balena0 Link encap:Ethernet HWaddr 02:42:83:5E:26:AC
inet addr:10.114.101.1 Bcast:10.114.101.255 Mask:255.255.255.0
--
br-233ab2d0cdb1 Link encap:Ethernet HWaddr 02:42:DE:0E:DC:2A
inet addr:172.17.0.1 Bcast:172.17.255.255 Mask:255.255.0.0
inet6 addr: fe80::42:deff:fe0e:dc2a/64 Scope:Link
--
eth0 Link encap:Ethernet HWaddr DC:A6:32:E8:C9:56
inet addr:192.168.1.127 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::aa2f:7f31:b094:9181/64 Scope:Link
inet6 addr: fd25:36da:e8ec::e1d/128 Scope:Global
inet6 addr: fd25:36da:e8ec:0:99aa:a2bd:39d5:f53f/64 Scope:Global
--
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
--
resin-dns Link encap:Ethernet HWaddr 2E:ED:31:EB:05:35
inet addr:10.114.102.1 Bcast:0.0.0.0 Mask:255.255.255.0
--
resin-vpn Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:10.246.34.90 P-t-P:52.4.252.97 Mask:255.255.255.255
inet6 addr: fe80::a238:945a:e93b:c106/64 Scope:Link
--
supervisor0 Link encap:Ethernet HWaddr 02:42:58:E8:D0:F7
inet addr:10.114.104.1 Bcast:10.114.104.127 Mask:255.255.255.128
--
veth43d6399 Link encap:Ethernet HWaddr AA:CC:21:F4:A0:E6
inet6 addr: fe80::a8cc:21ff:fef4:a0e6/64 Scope:Link
--
wwp1s0u1u1i4 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
inet addr:100.56.81.95 P-t-P:100.65.50.81 Mask:255.255.255.252
The READING_INTERVAL_SEC variable is the interval between metrics readings, in seconds. The default interval is 300 seconds or 5 minutes.