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@@ -70,8 +70,8 @@ NOTE: If you installed Elasticsearch using a package (.deb, .rpm) this setting w
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[[setup-configuration-memory]]
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==== Memory Settings
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-The Linux kernel tries to use as much memory as possible for file system
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-caches and eagerly swaps out unused application memory, possibly resulting
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+Most operating systems try to use as much memory as possible for file system
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+caches and eagerly swap out unused application memory, possibly resulting
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in the elasticsearch process being swapped. Swapping is very bad for
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performance and for node stability, so it should be avoided at all costs.
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@@ -84,10 +84,16 @@ There are three options:
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The simplest option is to completely disable swap. Usually Elasticsearch
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is the only service running on a box, and its memory usage is controlled
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by the `ES_HEAP_SIZE` environment variable. There should be no need
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-to have swap enabled. On Linux systems, you can disable swap temporarily
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+to have swap enabled.
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+
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+On Linux systems, you can disable swap temporarily
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by running: `sudo swapoff -a`. To disable it permanently, you will need
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to edit the `/etc/fstab` file and comment out any lines that contain the
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word `swap`.
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+
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+On Windows, the equivalent can be achieved by disabling the paging file entirely
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+via `System Properties → Advanced → Performance → Advanced → Virtual memory`.
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+
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--
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* **Configure `swappiness`**
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@@ -107,8 +113,8 @@ emergencies.
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* **`mlockall`**
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+
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--
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-The third option on Linux/Unix systems only, is to use
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-http://opengroup.org/onlinepubs/007908799/xsh/mlockall.html[mlockall] to
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+The third option is to use
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+http://opengroup.org/onlinepubs/007908799/xsh/mlockall.html[mlockall] on Linux/Unix systems, or https://msdn.microsoft.com/en-us/library/windows/desktop/aa366895%28v=vs.85%29.aspx[VirtualLock] on Windows, to
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try to lock the process address space into RAM, preventing any Elasticsearch
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memory from being swapped out. This can be done, by adding this line
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to the `config/elasticsearch.yml` file:
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@@ -128,9 +134,9 @@ curl http://localhost:9200/_nodes/process?pretty
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--------------
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If you see that `mlockall` is `false`, then it means that the the `mlockall`
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-request has failed. The most probable reason is that the user running
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-Elasticsearch doesn't have permission to lock memory. This can be granted
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-by running `ulimit -l unlimited` as `root` before starting Elasticsearch.
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+request has failed. The most probable reason, on Linux/Unix systems, is that
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+the user running Elasticsearch doesn't have permission to lock memory. This can
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+be granted by running `ulimit -l unlimited` as `root` before starting Elasticsearch.
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Another possible reason why `mlockall` can fail is that the temporary directory
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(usually `/tmp`) is mounted with the `noexec` option. This can be solved by
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gmarz