b6054473e · cryptotaxi247/netdata-1

@@ -26,7 +26,7 @@ and **virtual machines** spawn by managers that register them with cgroups (qemu

26 In general, no additional settings are required. Netdata discovers all available cgroups on the host system and

27 collects their metrics.

28

29 -### how Netdata finds the available cgroups

29 +### How Netdata finds the available cgroups

30

31 Linux exposes resource usage reporting and provides dynamic configuration for cgroups, using virtual files (usually)

32 under `/sys/fs/cgroup`. Netdata reads `/proc/self/mountinfo` to detect the exact mount point of cgroups. Netdata also

@@ -43,7 +43,7 @@ allows manual configuration of this mount point, using these settings:

43

44 Netdata rescans these directories for added or removed cgroups every `check for new cgroups every` seconds.

45

46 -### hierarchical search for cgroups

46 +### Hierarchical search for cgroups

47

48 Since cgroups are hierarchical, for each of the directories shown above, Netdata walks through the subdirectories

49 recursively searching for cgroups (each subdirectory is another cgroup).

@@ -61,7 +61,7 @@ cgroups ([systemd services are monitored by Netdata](#monitoring-systemd-service

61 desktop and remote user sessions), qemu virtual machines (child cgroups of virtual machines) and `init.scope`. All

62 others are enabled.

63

64 -### unified cgroups (cgroups v2) support

64 +### Unified cgroups (cgroups v2) support

65

66 Netdata automatically detects cgroups version. If detection fails Netdata assumes v1.

67 To switch to v2 manually add:

@@ -75,19 +75,19 @@ To switch to v2 manually add:

75 Unified cgroups use same name pattern matching as v1 cgroups. `cgroup_enable_systemd_services_detailed_memory` is

76 currently unsupported when using unified cgroups.

77

78 -### enabled cgroups

78 +### Enabled cgroups

79

80 To provide a sane default, Netdata uses the

81 following [pattern list](https://github.com/netdata/netdata/blob/master/libnetdata/simple_pattern/README.md):

82

83 -- checks the pattern against the path of the cgroup

83 +- Checks the pattern against the path of the cgroup

84

85 ```text

86 [plugin:cgroups]

87 enable by default cgroups matching = !*/init.scope *.scope !*/vcpu* !*/emulator !*.mount !*.partition !*.service !*.slice !*.swap !*.user !/ !/docker !/libvirt !/lxc !/lxc/*/ns !/lxc/*/ns/* !/machine !/qemu !/system !/systemd !/user *

88 ```

89

90 -- checks the pattern against the name of the cgroup (as you see it on the dashboard)

90 +- Checks the pattern against the name of the cgroup (as you see it on the dashboard)

91

92 ```text

93 [plugin:cgroups]

@@ -123,7 +123,7 @@ will have to adjust the configuration).

123 [docker-socket-proxy](https://github.com/Tecnativa/docker-socket-proxy) can also be used to give Netdata restricted

124 access to the socket. Note that `PODMAN_HOST` in Netdata's environment should be set to the proxy's URL in this case.

125

126 -### charts with zero metrics

126 +### Charts with zero metrics

127

128 By default, Netdata will enable monitoring metrics only when they are not zero. If they are constantly zero they are

129 ignored. Metrics that will start having values, after Netdata is started, will be detected and charts will be

@@ -138,7 +138,7 @@ chart instead of `auto` to enable it permanently. For example:

138 You can also set the `enable zero metrics` option to `yes` in the `[global]` section which enables charts with zero

139 metrics for all internal Netdata plugins.

140

141 -### alarms

141 +### Alarms

142

143 CPU and memory limits are watched and used to rise alarms. Memory usage for every cgroup is checked against `ram`

144 and `ram+swap` limits. CPU usage for every cgroup is checked against `cpuset.cpus` and `cpu.cfs_period_us` + `cpu.cfs_quota_us` pair assigned for the cgroup. Configuration for the alarms is available in `health.d/cgroups.conf`

@@ -190,7 +190,7 @@ Support per distribution:

190 - Merged disk read operations

191 - Merged disk write operations

192

193 -### how to enable cgroup accounting on systemd systems that is by default disabled

193 +### How to enable cgroup accounting on systemd systems that is by default disabled

194

195 You can verify there is no accounting enabled, by running `systemd-cgtop`. The program will show only resources for

196 cgroup `/`, but all services will show nothing.

@@ -259,28 +259,17 @@ Which systemd services are monitored by Netdata is determined by the following p

259 Netdata monitors containers automatically when it is installed at the host, or when it is installed in a container that

260 has access to the `/proc` and `/sys` filesystems of the host.

261

262 -Netdata prior to v1.6 had 2 issues when such containers were monitored:

262 +Network interfaces and cgroups (containers) are self-cleaned. When a network interface or container stops, Netdata might log

263 +a few errors in error.log complaining about files it cannot find, but immediately:

264

264 -1. network interface alarms where triggering when containers were stopped

265 -

266 -2. charts were never cleaned up, so after some time dozens of containers were showing up on the dashboard, and they were

267 - occupying memory.

268 -

269 -### the current Netdata

270 -

271 -network interfaces and cgroups (containers) are now self-cleaned.

272 -

273 -So, when a network interface or container stops, Netdata might log a few errors in error.log complaining about files it

274 -cannot find, but immediately:

275 -

276 -1. it will detect this is a removed container or network interface

277 -2. it will freeze/pause all alarms for them

278 -3. it will mark their charts as obsolete

279 -4. obsolete charts are not be offered on new dashboard sessions (so hit F5 and the charts are gone)

280 -5. existing dashboard sessions will continue to see them, but of course they will not refresh

281 -6. obsolete charts will be removed from memory, 1 hour after the last user viewed them (configurable

265 +1. It will detect this is a removed container or network interface

266 +2. It will freeze/pause all alarms for them

267 +3. It will mark their charts as obsolete

268 +4. Obsolete charts are not be offered on new dashboard sessions (so hit F5 and the charts are gone)

269 +5. Existing dashboard sessions will continue to see them, but of course they will not refresh

270 +6. Obsolete charts will be removed from memory, 1 hour after the last user viewed them (configurable

271 with `[global].cleanup obsolete charts after seconds = 3600` (at `netdata.conf`).

283 -7. when obsolete charts are removed from memory they are also deleted from disk (configurable

272 +7. When obsolete charts are removed from memory they are also deleted from disk (configurable

273 with `[global].delete obsolete charts files = yes`)

274

275 ### Monitored container metrics

Fix doc capitalization and remove obsolete section (#14569)