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Diffstat (limited to 'daemon/README.md')
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diff --git a/daemon/README.md b/daemon/README.md index 1ea865f89..44abfa8e9 100644 --- a/daemon/README.md +++ b/daemon/README.md @@ -254,57 +254,14 @@ where: See [debugging](#debugging). -## OOM Score - -Netdata runs with `OOMScore = 1000`. This means Netdata will be the first to be killed when your server runs out of -memory. - -You can set Netdata OOMScore in `netdata.conf`, like this: - -```conf -[global] - OOM score = 1000 -``` - -Netdata logs its OOM score when it starts: - -```sh -# grep OOM /var/log/netdata/error.log -2017-10-15 03:47:31: netdata INFO : Adjusted my Out-Of-Memory (OOM) score from 0 to 1000. -``` - -### OOM score and systemd - -Netdata will not be able to lower its OOM Score below zero, when it is started as the `netdata` user (systemd case). - -To allow Netdata control its OOM Score in such cases, you will need to edit `netdata.service` and set: - -```sh -[Service] -# The minimum Netdata Out-Of-Memory (OOM) score. -# Netdata (via [global].OOM score in netdata.conf) can only increase the value set here. -# To decrease it, set the minimum here and set the same or a higher value in netdata.conf. -# Valid values: -1000 (never kill netdata) to 1000 (always kill netdata). -OOMScoreAdjust=-1000 -``` - -Run `systemctl daemon-reload` to reload these changes. - -The above, sets and OOMScore for Netdata to `-1000`, so that Netdata can increase it via `netdata.conf`. - -If you want to control it entirely via systemd, you can set in `netdata.conf`: - -```conf -[global] - OOM score = keep -``` - -Using the above, whatever OOM Score you have set at `netdata.service` will be maintained by netdata. - ## Netdata process scheduling policy -By default Netdata runs with the `idle` process scheduling policy, so that it uses CPU resources, only when there is -idle CPU to spare. On very busy servers (or weak servers), this can lead to gaps on the charts. +By default Netdata versions prior to 1.34.0 run with the `idle` process scheduling policy, so that it uses CPU +resources, only when there is idle CPU to spare. On very busy servers (or weak servers), this can lead to gaps on +the charts. + +Starting with version 1.34.0, Netdata instead uses the `batch` scheduling policy by default. This largely eliminates +issues with gaps in charts on busy systems while still keeping the impact on the rest of the system low. You can set Netdata scheduling policy in `netdata.conf`, like this: @@ -315,9 +272,9 @@ You can set Netdata scheduling policy in `netdata.conf`, like this: You can use the following: -| policy | description | +| policy | description | | :-----------------------: | :---------- | -| `idle` | use CPU only when there is spare - this is lower than nice 19 - it is the default for Netdata and it is so low that Netdata will run in "slow motion" under extreme system load, resulting in short (1-2 seconds) gaps at the charts. | +| `idle` | use CPU only when there is spare - this is lower than nice 19 - it is the default for Netdata and it is so low that Netdata will run in "slow motion" under extreme system load, resulting in short (1-2 seconds) gaps at the charts. | | `other`<br/>or<br/>`nice` | this is the default policy for all processes under Linux. It provides dynamic priorities based on the `nice` level of each process. Check below for setting this `nice` level for netdata. | | `batch` | This policy is similar to `other` in that it schedules the thread according to its dynamic priority (based on the `nice` value). The difference is that this policy will cause the scheduler to always assume that the thread is CPU-intensive. Consequently, the scheduler will apply a small scheduling penalty with respect to wake-up behavior, so that this thread is mildly disfavored in scheduling decisions. | | `fifo` | `fifo` can be used only with static priorities higher than 0, which means that when a `fifo` threads becomes runnable, it will always immediately preempt any currently running `other`, `batch`, or `idle` thread. `fifo` is a simple scheduling algorithm without time slicing. | @@ -551,4 +508,4 @@ valgrind $(which netdata) -D Netdata will start and it will be a lot slower. Now reproduce the crash and `valgrind` will dump on your console the stack trace. Open a new github issue and post the output. -[](<>) + |