Advanced configuration

Besides the standard options available, PyCharm enables you to perform low-level configuration of the underlying platform and the Java runtime.

JVM options

PyCharm runs on the Java Virtual Machine (JVM), which has various options that control its performance. The default options used to run PyCharm are specified in the following file:

<IDE_HOME>\bin\pycharm64.exe.vmoptions

PyCharm.app/Contents/bin/pycharm.vmoptions

<IDE_HOME>/bin/pycharm64.vmoptions (for the default 64-bit JVM)

<IDE_HOME>/bin/pycharm.vmoptions (for the optional 32-bit JVM)

Configure JVM options

Do one of the following to create a copy of the default file with JVM options in the configuration directory that will override the original file:

On the Help menu, click Edit Custom VM Options.
If you do not have any project open, on the Welcome screen, click Configure and then Edit Custom VM Options.
If you cannot start PyCharm, manually copy the default file with JVM options to the PyCharm configuration directory.

If you do not have write access to the PyCharm configuration directory, you can add the PYCHARM_VM_OPTIONS environment variable to specify the location of the file with your preferred JVM options. This file will override both the original default file and the copy located in the PyCharm configuration directory.

Common options

The default values of the JVM options should be optimal in most cases. The following are the most commonly modified ones:

Option	Description
`-Xmx`	Limits the maximum memory heap size that the JVM can allocate for running PyCharm. Default value depends on the platform. If you are experiencing slowdowns, you may want to increase this value, for example, to set the value to 2048 megabytes, change this option to `-Xmx2048m`.
`-Xms`	Specifies the initial memory allocated by the JVM for running PyCharm. Default value depends on the platform. It is usually set to about half of the maximum allowed memory (-Xmx), for example, `-Xms1024m`.
`-XX:NewRatio`	Specifies the ratio between the size of the young and old generation of the heap. In most cases, a ratio between 2 and 4 is recommended. This will set the size of the young generation to be 1/2 to 1/4 of the old generation correspondingly, which is good when you are often working on one project and only a few files at a time. However, if you are constantly opening new files and switching between several projects, you may need to increase the young generation. In this case, try setting `-XX:NewRatio=1`, which will make the young generation as large as the old generation, allowing objects to remain in the young generation for longer.

For more information about available JVM options, see the java reference for Windows or macOS/Linux.

Platform properties

PyCharm enables you to customize various platform-specific properties, such as the path to user-installed plugins and the maximum supported file size. The default properties used to run PyCharm are specified in the following file:

<IDE_HOME>\bin\idea.properties

PyCharm.app/Contents/bin/idea.properties

<IDE_HOME>/bin/idea.properties

Configure platform properties:

Do one of the following to create an empty idea.properties file in the configuration directory that will override the values from the original file:

From the Help menu, select Edit Custom Properties.
If you do not have any project open, on the Welcome screen, click Configure and then select Edit Custom Properties.
If you cannot start PyCharm, manually create an empty idea.properties file in the PyCharm configuration directory.

If you do not have write access to the PyCharm configuration directory, you can add the PYCHARM_PROPERTIES environment variable to specify the location of the idea.properties file. The properties in this file will override the corresponding properties in both the original default file and the one located in the PyCharm configuration directory.

Common properties

Users often change the following properties:

The default IDE directories may need to be moved, for example, if the user profile drive runs out of space or it is located on a slow disk, if the home directory is encrypted (slowing down the IDE) or located on a network drive, if you want to create a portable installation or exclude caches from home directory backups, and so on.
Property Path to
idea.config.path Configuration directory
idea.system.path System directory
idea.plugins.path Plugins directory
idea.log.path Logs directory
Specify paths with forward slashes /, including Windows paths (for example, C:/idea/system).
You can insert properties as variables. For example, use ${user.home} (standard Java system property) to specify paths relative to the user's home directory:
idea.config.path=${user.home}/MyIdeaConfiguration

Property	Path to
`idea.config.path`	Configuration directory
`idea.system.path`	System directory
`idea.plugins.path`	Plugins directory
`idea.log.path`	Logs directory

Limits that can affect performance:

Property	Description
`idea.max.content.load.filesize`	Maximum size of files (in kilobytes) that PyCharm is able to open. Working with large files can affect editor performance and increase memory consumption. The default value is `20000`.
`idea.max.intellisense.filesize`	Maximum size of files (in kilobytes) for which PyCharm provides coding assistance. Coding assistance for large files can affect editor performance and increase memory consumption. The default value is `2500`.
`idea.cycle.buffer`	Maximum size of the console cyclic buffer (in kilobytes). If the console output size exceeds this value, the oldest lines are deleted. To disable the cyclic buffer, set `idea.cycle.buffer.size=disabled`.
`idea.max.vcs.loaded.size.kb`	Maximum size (in kilobytes) that PyCharm loads for showing past file contents when comparing changes. The default value is `20480`.

PyCharm provides a number of other properties that define interaction with the environment (window managers, launchers, file system, and so on). Most of them act like hidden settings (in the sense that they are not evidently exposed), which you may need to enable or disable in certain cases. Change these properties only if advised by JetBrains Support.

Default IDE directories

By default, PyCharm stores user-specific files (configuration, caches, plugins, logs, and so on) in the user's home directory. However, you can change the location for storing those files, if necessary.

Configuration directory

The PyCharm configuration directory contains user-defined IDE settings, such as keymaps, color schemes, custom VM options, platform properties, and so on.

Syntax: %APPDATA%\JetBrains\<product><version>
Example: C:\Users\JohnS\AppData\Roaming\JetBrains\PyCharm2021.1

Syntax: ~/Library/Application Support/JetBrains/<product><version>
Example: ~/Library/Application Support/JetBrains/PyCharm2021.1

Syntax: ~/.config/JetBrains/<product><version>
Example: ~/.config/JetBrains/PyCharm2021.1

You can change the location of the PyCharm configuration directory using the idea.config.path property.

To share your personal IDE settings, copy the files from the configuration directory to the corresponding folders on another PyCharm installation. Make sure that PyCharm is not running to avoid erasing the copied files when you shut down the IDE.

System directory

The PyCharm system directory contains caches and local history files.

Syntax: %LOCALAPPDATA%\JetBrains\<product><version>
Example: C:\Users\JohnS\AppData\Local\JetBrains\PyCharm2021.1

Syntax: ~/Library/Caches/JetBrains/<product><version>
Example: ~/Library/Caches/JetBrains/PyCharm2021.1

Syntax: ~/.cache/JetBrains/<product><version>
Example: ~/.cache/JetBrains/PyCharm2021.1

You can change the location of the PyCharm system directory using the idea.system.path property.

Plugins directory

The PyCharm plugins directory contains user-installed plugins.

Syntax: %APPDATA%\JetBrains\<product><version>\plugins
Example: C:\Users\JohnS\AppData\Roaming\JetBrains\PyCharm2021.1\plugins

Syntax: ~/Library/Application Support/JetBrains/<product><version>/plugins
Example: ~/Library/Application Support/JetBrains/PyCharm2021.1/plugins

Syntax: ~/.local/share/JetBrains/<product><version>
Example: ~/.local/share/JetBrains/PyCharm2021.1

You can change the location of the PyCharm plugins directory using the idea.plugins.path property.

Logs directory

The PyCharm logs directory contains product logs and thread dumps.

Syntax: %LOCALAPPDATA%\JetBrains\<product><version>\log
Example: C:\Users\JohnS\AppData\Local\JetBrains\PyCharm2021.1\log

Syntax: ~/Library/Logs/JetBrains/<product><version>
Example: ~/Library/Logs/JetBrains/PyCharm2021.1

Syntax: ~/.cache/JetBrains/<product><version>/log
Example: ~/.cache/JetBrains/PyCharm2021.1/log

You can change the location of the PyCharm logs directory using the idea.log.path property.

Last modified: 08 April 2021