From 2e85f9325a797977eea9dfea0a925775ddd211d9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Feb 2021 12:49:00 +0100 Subject: Merging upstream version 1.29.0. Signed-off-by: Daniel Baumann --- docs/guides/configure/performance.md | 235 +++++++++++++++++++++++++++++++++++ 1 file changed, 235 insertions(+) create mode 100644 docs/guides/configure/performance.md (limited to 'docs/guides/configure') diff --git a/docs/guides/configure/performance.md b/docs/guides/configure/performance.md new file mode 100644 index 000000000..5f93a8cd4 --- /dev/null +++ b/docs/guides/configure/performance.md @@ -0,0 +1,235 @@ + + +# How to optimize the Netdata Agent's performance + +We designed the Netdata Agent to be incredibly lightweight, even when it's collecting a few thousand dimensions every +second and visualizing that data into hundreds of charts. The Agent itself should never use more than 1% of a single CPU +core, roughly 100 MiB of RAM, and minimal disk I/O to collect, store, and visualize all this data. + +We take this scalability seriously. We have one user [running +Netdata](https://github.com/netdata/netdata/issues/1323#issuecomment-266427841) on a system with 144 cores and 288 +threads. Despite collecting 100,000 metrics every second, the Agent still only uses 9% CPU utilization on a +single core. + +But not everyone has such powerful systems at their disposal. For example, you might run the Agent on a cloud VM with +only 512 MiB of RAM, or an IoT device like a [Raspberry Pi](/docs/guides/monitor/pi-hole-raspberry-pi.md). In these +cases, reducing Netdata's footprint beyond its already diminutive size can pay big dividends, giving your services more +horsepower while still monitoring the health and the performance of the node, OS, hardware, and applications. + +## Prerequisites + +- A node running the Netdata Agent. +- Familiarity with configuring the Netdata Agent with `edit-config`. + +If you're not familiar with how to configure the Netdata Agent, read our [node configuration +doc](/docs/configure/nodes.md) before continuing with this guide. This guide assumes familiarity with the Netdata config +directory, using `edit-config`, and the process of uncommenting/editing various settings in `netdata.conf` and other +configuration files. + +## What affects Netdata's performance? + +Netdata's performance is primarily affected by **data collection/retention** and **clients accessing data**. + +You can configure almost all aspects of data collection/retention, and certain aspects of clients accessing data. For +example, you can't control how many users might be viewing a local Agent dashboard, [viewing an +infrastructure](/docs/visualize/overview-infrastructure.md) in real-time with Netdata Cloud, or running [Metric +Correlations](https://learn.netdata.cloud/docs/cloud/insights/metric-correlations). + +The Netdata Agent runs with the lowest possible [process scheduling +policy](/daemon/README.md#netdata-process-scheduling-policy), which is `nice 19`, and uses the `idle` process scheduler. +Together, these settings ensure that the Agent only gets CPU resources when the node has CPU resources to space. If the +node reaches 100% CPU utilization, the Agent is stopped first to ensure your applications get any available resources. +In addition, under heavy load, collectors that require disk I/O may stop and show gaps in charts. + +Let's walk through the best ways to improve the Netdata Agent's performance. + +## Reduce collection frequency + +The fastest way to improve the Agent's resource utilization is to reduce how often it collects metrics. + +### Global + +If you don't need per-second metrics, or if the Netdata Agent uses a lot of CPU even when no one is viewing that node's +dashboard, configure the Agent to collect metrics less often. + +Open `netdata.conf` and edit the `update every` setting. The default is `1`, meaning that the Agent collects metrics +every second. + +If you change this to `2`, Netdata enforces a minimum `update every` setting of 2 seconds, and collects metrics every +other second, which will effectively halve CPU utilization. Set this to `5` or `10` to collect metrics every 5 or 10 +seconds, respectively. + +```conf +[global] + update every = 5 +``` + +### Specific plugin or collector + +Every collector and plugin has its own `update every` setting, which you can also change in the `go.d.conf`, +`python.d.conf`, `node.d.conf`, or `charts.d.conf` files, or in individual collector configuration files. If the `update +every` for an individual collector is less than the global, the Netdata Agent uses the global setting. See the [enable +or configure a collector](/docs/collect/enable-configure.md) doc for details. + +To reduce the frequency of an [internal +plugin/collector](/docs/collect/how-collectors-work.md#collector-architecture-and-terminology), open `netdata.conf` and +find the appropriate section. For example, to reduce the frequency of the `apps` plugin, which collects and visualizes +metrics on application resource utilization: + +```conf +[plugin:apps] + update every = 5 +``` + +To [configure an individual collector](/docs/collect/enable-configure.md), open its specific configuration file with +`edit-config` and look for the `update_every` setting. For example, to reduce the frequency of the `nginx` collector, +run `sudo ./edit-config go.d/nginx.conf`: + +```conf +# [ GLOBAL ] +update_every: 10 +``` + +## Disable unneeded plugins or collectors + +If you know that you don't need an [entire plugin or a specific +collector](/docs/collect/how-collectors-work.md#collector-architecture-and-terminology), you can disable any of them. +Keep in mind that if a plugin/collector has nothing to do, it simply shuts down and does not consume system resources. +You will only improve the Agent's performance by disabling plugins/collectors that are actively collecting metrics. + +Open `netdata.conf` and scroll down to the `[plugins]` section. To disable any plugin, uncomment it and set the value to +`no`. For example, to explicitly keep the `proc` and `go.d` plugins enabled while disabling `python.d`, `charts.d`, and +`node.d`. + +```conf +[plugins] + proc = yes + python.d = no + charts.d = no + node.d = no + go.d = yes +``` + +Disable specific collectors by opening their respective plugin configuration files, uncommenting the line for the +collector, and setting its value to `no`. + +```bash +sudo ./edit-config go.d.conf +sudo ./edit-config python.d.conf +sudo ./edit-config node.d.conf +sudo ./edit-config charts.d.conf +``` + +For example, to disable a few Python collectors: + +```conf +modules: + apache: no + dockerd: no + fail2ban: no +``` + +## Lower memory usage for metrics retention + +Reduce the disk space that the [database engine](/database/engine/README.md) uses to retain metrics by editing +the `dbengine multihost disk space` option in `netdata.conf`. The default value is `256`, but can be set to a minimum of +`64`. By reducing the disk space allocation, Netdata also needs to store less metadata in the node's memory. + +The `page cache size` option also directly impacts Netdata's memory usage, but has a minimum value of `32`. + +Reducing the value of `dbengine multihost disk space` does slim down Netdata's resource usage, but it also reduces how +long Netdata retains metrics. Find the right balance of performance and metrics retention by using the [dbengine +calculator](/docs/store/change-metrics-storage.md#calculate-the-system-resources-ram-disk-space-needed-to-store-metrics). + +All the settings are found in the `[global]` section of `netdata.conf`: + +```conf +[global] + memory mode = dbengine + page cache size = 32 + dbengine multihost disk space = 256 +``` + +## Run Netdata behind Nginx + +A dedicated web server like Nginx provides far more robustness than the Agent's internal [web server](/web/README.md). +Nginx can handle more concurrent connections, reuse idle connections, and use fast gzip compression to reduce payloads. + +For details on installing Nginx as a proxy for the local Agent dashboard, see our [Nginx +doc](/docs/Running-behind-nginx.md). + +After you complete Nginx setup according to the doc linked above, we recommend setting `keepalive` to `1024`, and using +gzip compression with the following options in the `location /` block: + +```conf + location / { + ... + gzip on; + gzip_proxied any; + gzip_types *; + } +``` + +Finally, edit `netdata.conf` with the following settings: + +```conf +[global] + bind socket to IP = 127.0.0.1 + access log = none + disconnect idle web clients after seconds = 3600 + enable web responses gzip compression = no +``` + +## Disable/lower gzip compression for the dashboard + +If you choose not to run the Agent behind Nginx, you can disable or lower the Agent's web server's gzip compression. +While gzip compression does reduce the size of the HTML/CSS/JS payload, it does use additional CPU while a user is +looking at the local Agent dashboard. + +To disable gzip compression, open `netdata.conf` and find the `[web]` section: + +```conf +[web] + enable gzip compression = no +``` + +Or to lower the default compression level: + +```conf +[web] + enable gzip compression = yes + gzip compression level = 1 +``` + +## Disable logs + +If you installation is working correctly, and you're not actively auditing Netdata's logs, disable them in +`netdata.conf`. + +```conf +[global] + debug log = none + error log = none + access log = none +``` + +## What's next? + +We hope this guide helped you better understand how to optimize the performance of the Netdata Agent. + +Now that your Agent is running smoothly, we recommend you [secure your nodes](/docs/configure/nodes.md) if you haven't +already. + +Next, dive into some of Netdata's more complex features, such as configuring its health watchdog or exporting metrics to +an external time-series database. + +- [Interact with dashboards and charts](/docs/visualize/interact-dashboards-charts.md) +- [Configure health alarms](/docs/monitor/configure-alarms.md) +- [Export metrics to external time-series databases](/docs/export/external-databases.md) + +[![analytics](https://www.google-analytics.com/collect?v=1&aip=1&t=pageview&_s=1&ds=github&dr=https%3A%2F%2Fgithub.com%2Fnetdata%2Fnetdata&dl=https%3A%2F%2Fmy-netdata.io%2Fgithub%2Fdocs%2Fguides%2Fconfigure%2Fperformance.md&_u=MAC~&cid=5792dfd7-8dc4-476b-af31-da2fdb9f93d2&tid=UA-64295674-3)](<>) -- cgit v1.2.3