Environment Variables
Installation
Note
These variables are read-only and automatically set by Katana on start up.
KATANA_RELEASE
The externally visible version displayed in the UI. (For example, 4.0v1.)
KATANA_VERSION
Katana’s internal version number, which is used for things like upgrade scripts. As this is principally an implementation detail,
KATANA_RELEASE
should usually be used instead.KATANA_ROOT
Katana’s installation directory.
KATANA_DEFAULT_RESOURCES
The path used for internal default resources. Default resources can be overridden by resources in
KATANA_RESOURCES
directories.
Launch Mode
Note
These variables are read-only and automatically set by Katana on start
up. They can only be accessed through the Configuration
module, e.g.
Configuration.get('KATANA_UI_MODE')
.
KATANA_BATCH_MODE
Defined when Katana is running in batch mode (
--batch
).KATANA_SCRIPT_MODE
Defined when Katana is running in script mode (
--script
).KATANA_SHELL_MODE
Defined when Katana is running in shell mode (
--shell
).KATANA_UI_MODE
Defined when Katana is running in UI mode.
Plug-ins and Configuration
KATANA_RESOURCES
List of paths from which Katana plug-ins are loaded, separated by the OS-specific path separator (
:
on Linux,;
on Windows).KATANA_TAGLINE
Text to display in the splash screen and the About Katana dialog.
KATANA_SPLASH_IMAGE_FILE
✨ New in Katana 4.5v1The filename of an image to show in the splash screen and the About Katana dialog.
The default size of the Katana splash screen image is 700 × 318 pixels.
Supports alpha channels.
Supports animated GIFs to some extent (see note below).
Supports animated WebP images to some extent (see note below). ✨ New in Katana 7.5v1
Can be a list of image filenames separated by the OS-specific path separator, in which case one of the images will be chosen at random, for example:
export KATANA_SPLASH_IMAGE_FILE=~/Pictures/taco.png:~/Pictures/bell.gif export KATANA_SPLASH_IMAGE_FILE=`ls /path/to/splash_screens/*.png | tr '\n' ':'`
Note
While animated GIF and WebP images are supported by
KATANA_SPLASH_IMAGE_FILE
, they will not play back smoothly in the splash screen, as processing during startup focuses on launching Katana, rather than playing back a GIF. The animated image will be played back smoothly in the About Katana dialog though.KATANA_SPLASH_CREDIT_NAME
A name to display after “Artwork by” on the splash screen and About Katana dialog. When set to
0
, no credit will be displayed.KATANA_USER_RESOURCE_DIRECTORY
Path from which user settings are loaded. User settings include preferences, layouts, and user-defined macros, shelf scripts, startup scripts, and so forth. If not set, user settings are loaded from a directory named
.katana
in the user’s home directory.KATANA_NODETYPETAB_NODETYPES
Comma-separated list of node type names that determines which tabs are available under the Tabs > Node menu. Node Type Tabs show parameters for specific types of nodes.
KATANA_LOG_CONFIG
Path to logger configuration file.
KATANA_DEFAULT_ASSET_PLUGIN
The name of the default asset plug-in. If not defined, the default is
File
.KATANA_DEFAULT_FILE_SEQUENCE_PLUGIN
The name of the default file sequence plug-in. If not defined, the default is
FileSeq
.KATANA_HYDRAVIEWER_DEBUG
A flag that, if non-zero, will enable logging for custom Hydra Render Delegates.
FNPXR_PLUGINPATH
Equivalent of the stock USD
PXR_PLUGINPATH_NAME
environment variable for locating USD plug-ins to be loaded by Katana’s namespaced USD library (used by the Viewer and the bundled Katana USD plug-ins). See Building Katana USD Plug-ins.KATANA_USD_PLUGINS_DISABLED
Disables the startup environment setup for the KatanaUsdPlugins shipped with Katana by default. This will be required to set to
1
if you would like to use your own KatanaUsdPlugins, as two sets of Plugins cannot be used at the same time.
Python Search Path
Katana’s search paths for Python module files are built from different parts:
KATANA_DEBUG_PRE_PYTHONPATH
(user-defined)Katana’s own default search paths.
PYTHONPATH
(user-defined) and site-specific configuration viasitecustomize.py
(user-defined)KATANA_POST_PYTHONPATH
(user-defined)
Each of these parts is a list of filesystem paths, separated by the OS-specific
path separator (colon :
on Linux, semicolon ;
on Windows).
The combined Python search paths are made available in the
KATANA_INTERNAL_PYTHONPATH
environment variable that is set by Katana.
That variable is used to override the paths for the Python interpreter inside
of renderboot
when renderboot
is started, after the Python interpreter
is initialized.
Note that sys.path
may contain additional paths as a result of
plug-in startup scripts.
Note
The Katana Queue Daemon (KQD
) script and the Agent scripts that it
spawns are run in a Python interpreter that is initialized via
PYTHONPATH
, in addition to the following paths:
$KATANA_ROOT/plugins/Resources/Core/Plugins/
– so thatKQD
can import thekq
Python package of Katana Queue$KATANA_ROOT/bin/python/
– so thatKQD
can import thezmq
third-party Python package
Caution
KATANA_DEBUG_PRE_PYTHONPATH
is meant to be used for debugging purposes
only, as it may lead to unexpected application behavior due to
non-supported modules loaded in place of the application’s ones.
Rendering
DEFAULT_RENDER_TERMINATION_SIGNAL
On Linux, Katana uses signals to terminate the renderboot process. When a render is canceled, the module responsible for starting renderboot first checks for a specific environment variable, to determine which signal should be used.
Katana currently supports renderer-specific variables that are named
<renderer name>_RENDER_TERMINATION_SIGNAL
, for example,ARNOLD_RENDER_TERMINATION_SIGNAL
.Valid values for the variables are:
SIGABRT
,SIGKILL
,SIGTERM
. If no variable is set, the signal defaults toSIGTERM
. The module then useskill(pid, signal)
to terminate renderboot.ARNOLD_RENDER_TERMINATION_SIGNAL
See
DEFAULT_RENDER_TERMINATION_SIGNAL
. By default, during application startup,ARNOLD_RENDER_TERMINATION_SIGNAL
is initialised toSIGKILL
.PRMAN_RENDER_TERMINATION_SIGNAL
See
DEFAULT_RENDER_TERMINATION_SIGNAL
.KATANA_CANCELLED_RENDER_PROCESS_GRACE_PERIOD
✨ New in Katana 4.0v4The time (in seconds) that a cancelled render process is allowed to continue running before Katana terminates it definitively. Default is
60
seconds. This environment variable is most relevant when the defaultSIGTERM
signal is used inDEFAULT_RENDER_TERMINATION_SIGNAL
, since sending that signal to the process does not necessarily guarantee that the render process will terminate in a timely manner.DEFAULT_RENDERER
Default renderer. If not set, defaults to
dl
, the 3Delight renderer.KATANA_RENDER_TILE_SIZE
Global tile size to be used in the render system 2D. The variable is a scalar type used both for the width and height of the tile.
KATANA_RENDER_LOGFILE
Path where render log should be saved.
KATANA_CATALOG_REFRESH_RATE
Rate at which Katana’s Catalog subsystem will trigger a repaint event when new areas of the rendered image have been received from the renderer. Default is
100
(Hz).KATANA_TILE_FILENAME
Used for defining custom filenames and path of tiles created as part of a tile render. By default, a
"tile_<column>_<row>."
prefix is prepended to the original name of render file. Users can set this environment variable to customize the tile filename and filepath. The following wildcards can be used:@STEM@
@EXT@
(includes dot)@COLUMN@
@ROW@
@COLUMNS@
@ROWS@
@DEFAULT@
(equivalent totile_@COLUMN@_@ROW@.@STEM@@EXT@
)
For example, the following setup would append the tile column and row, as well as the total number of columns and rows, to the original name of render file:
"@STEM@_(@COLUMN@,@ROW@)_@COLUMNS@x@ROWS@@EXT@"
KATANA_DISPLAYDRIVER_PRECISION
✨ New in Katana 4The data type to use for encoding pixels that are transmitted between a render process and Katana. Can be used to reduce the bandwidth required for transmitting images, but at the cost of a loss of fidelity.
Choose between one of three options:
float
(default): Single-precision floating-point format (32 bits).half
: Half-precision floating-point format (16 bits).byte
: Reduced precision resulting in the lowest bandwidth, but possibly visible banding artifacts, and a loss of fidelity when stopping images up or down (8 bits). Clamps pixel values to a range between 0 and 1.
The value set by this environment variable can be overridden using the interactivePrecision parameter of RenderSettings nodes.
KATANA_DISABLE_FORESIGHT_PLUS
✨ New in Katana 4.5v1If set to
1
, disables Foresight+. Foresight+ provides a new, more efficient live rendering experience. Foresight+ sends lightweight Op Tree changes to the render process, rather than much larger scene graph changes that were previously calculated and sent to the render process.KATANA_LRUA_DEBUG
✨ New in Katana 4.5v1If set to a file path, enables live render update attribute (LRUA) debug logging. Each live render update attribute generated by the Foresight+ will be written to the log file and can be viewed in the Foresight Services tab. Live render update attribute logging is only available with Foresight+ live rendering.
GEOLIB_REMOTE_RUNTIME_REQUEST_DEADLINE
✨ New in Katana 4.5v1If set, overrides the default request timeout set by RPC clients when making requests to a remote runtime instance. Deadline should be specified as a positive integer in milliseconds.
KATANA_SERVICE_PROVIDER_DEADLINE
✨ New in Katana 4.5v1If set, overrides the default request timeout set by RPC clients when making requests to a service provider registry instance. Deadline should be specified as a positive integer in milliseconds.
GEOLIB_REMOTE_RUNTIME_CLIENT_DEBUG
✨ New in Katana 4.5v1If set, will result in each RPC client call to a remote runtime service to be logged (with its response time).
KATANA_LIVE_RENDERING_BATCH_UPDATES
✨ New in Katana 4.5v4If set to
1
, the render updates are sent as a single batch update. By default the render updates are streamed to the renderer plug-in as they become available.
Nuke Bridge
✨ New in Katana 4.5
KATANA_NUKE_EXECUTABLE
Path to a Nuke executable that should be used in Katana’s Nuke Bridge.
KATANA_NUKE_BRIDGE_DISABLED
If set, disables the automatic loading of the Nuke render plug-in. This doesn’t disable the Nuke Bridge tab itself, but without a valid render plug-in loaded, the tab’s contents will be disabled.
KATANA_NUKE_VERSION_OVERRIDE
If specified, the Nuke Bridge tab will not attempt to detect the version of the configured Nuke executable. For example, if set to
13.1
, the Nuke plug-ins for Nuke 13.1 will be used. Note that if the user-defined version override does not match the Nuke version, the required Nuke plug-ins may fail to load in Nuke.KATANA_NUKE_BRIDGE_MAXOUTPUTLAYERS
The maximum number of layers that KatanaWriter nodes in Nuke can deliver to Katana. Default is
20
.
Katana Queue (KQ)
✨ New in Katana 4
Katana Queue was added in Katana 4.0v1.
KQ_AGENT_ENVIRONMENT_FILE
Specifies the path to a file which is expected to contain a series of newline-separated name/value pairs of the form
name=value
, defining environment variables that will be exported verbatim to the Agent’s process environment when rendering with KQ.KQ_MINIMAL_AGENT_ENVIRONMENT
If set to
1
, initializes the environment in which Agent processes are launched to only contain names and values of variables that are set in Katana’sConfiguration
module, as well as a few other variables related to KQ. If not set, by default, Agent processes inherit the full environment from the Katana process, in addition to the minimal environment.KQ_DATA_ROOT
If set, specifies the path to a folder that KQ will use to store files related to rendering, such as Op tree files and render logs. By default, the value of
KATANA_TMPDIR
will be used.KQ_NUM_AGENTS
Specifies the number of local Agents KQ will spawn during application startup. Is expected to be a positive integer number, or
0
. Default is2
.The
kq.GetNumberOfLocalAgents()
function can be used to check how many local Agents are managed by the Katana Queue, as specified in this environment variable.KQ_DISABLED
✨ New in Katana 4.0v2If set to
1
, disables Katana Queue features by skipping the registration of the Katana Queue farm plug-in, and not starting the KQ Daemon (KQD
) process or any of KQ’s Agent processes during application startup.The
kq.IsDisabled()
function can be used to check whether KQ is disabled.Note
When disabling KQ, the Katana Queue tab will still be available in the UI, but will not list any KQ jobs for the duration of the Katana session.
KQ_OVERRIDE_KATANA_ROOT
✨ New in Katana 4.0v3By default KQ agents look for
renderboot
in the same installation directory as the artist workstation. In some circumstances, for example where KQ agents run remotely and Katana is installed in a different location on those hosts, the agents will fail to findrenderboot
.Setting this environment variable overrides this behaviour allowing you to set an arbitrary Katana installation directory that will be used when deploying render jobs to agents.
KQ_OVERRIDE_<renderer name>_PLUGIN_PATH
✨ New in Katana 4.0v3Similar to
KQ_OVERRIDE_KATANA_ROOT
,KQ_OVERRIDE_<renderer_name>_PLUGIN_PATH
provides a mechanism to specify an alternative installation path for renderer plugins, for example,KQ_OVERRIDE_ARNOLD_PLUGIN_PATH
specifies an alternative plugin directory for the Katana to Arnold plugin.
Color Management
KATANA_OCIO_LUT3D_EDGE_SIZE
Defines the edge size for the 3D texture used by Katana to store the OCIO LUT for color transformations. If not defined, the default is
64
.KATANA_OCIO_NO_FILMLOOK_COLORSPACE
OCIO color space to use when no filmlook transformation is enabled. This might be used to enable gamma correction even when no transform is specified. The name of the profile is specified by the environment variable.
Projects and Live Groups
KATANA_DISABLE_LIVEGROUP_CACHING
If defined, disables the storing of network contents in LiveGroup source files. This is useful when using projects with large numbers of deeply nested LiveGroups.
KATANA_DISABLE_LIVEGROUP_LOADING
If defined, disables loading live group contents from the network, and instead uses cached contents from the project file. This is useful in debugging or reconstructing old projects.
KATANA_NEVER_SHARE_LIVE_GROUPS
If defined, prevents LiveGroup nodes from being shared.
KATANA_ARCHIVE_AND_COMPRESS_LIVEGROUPS
If defined, forces Katana to archive and compress LiveGroup files on saving.
KATANA_NEVER_ARCHIVE_SCENE_FILE
If defined, prevents Katana from creating archives when saving project files or macros.
KATANA_NEVER_COMPRESS_SCENE_FILE
If defined, prevents Katana from compressing project files or macros on saving.
Crash Handling
KATANA_CRASH_HANDLING
Crash reporting allows you to submit crash dumps to The Foundry in the unlikely event of a crash. By default, crash reporting is enabled in GUI mode and disabled in terminal mode.
When
KATANA_CRASH_HANDLING
is set to1
, crash reporting is enabled in both GUI and terminal mode.When
KATANA_CRASH_HANDLING
is set to0
, crash reporting is disabled in both GUI and terminal mode.KATANA_NO_CRASH_PROMPT
When crash handling is enabled in GUI mode, this allows you to control whether reports are automatically submitted or not:
When
KATANA_NO_CRASH_PROMPT
is set to1
, crash reports are submitted automatically without displaying a crash reporter dialog.When
KATANA_NO_CRASH_PROMPT
is set to0
, Katana always displays a crash reporter dialog before submitting a crash report.
Caching and Temporary Files
KATANA_IMAGE_DISK_MEMORY
Maximum amount of swap disk memory usable by Katana while allocating image files, in megabytes. The default value is a fraction of available disk space in the temporary directory, or zero when Katana runs in batch mode.
KATANA_IMAGE_MEMORY
Maximum amount of runtime memory usable by Katana while allocating image memory, in megabytes. The default value is a fraction of available system memory.
KATANA_CATALOG_MEMORY_WARNING
✨ New in Katana 4.0v5Specify the memory usage threshold (as a percentage e.g.
70
would issue a warning when memory consumption reached 70% of the available RAM and disk space) above which a warning will be raised and further rendering will be suspended until memory is freed from the Catalog. By default this is 90% of the available RAM and disk space reserved for the Catalog.KATANA_HARD_MEMORY_LIMIT
✨ New in Katana 4.0v5If set, Katana will raise an un-recoverable
OutOfMemory
exception when it is unable to allocate image buffer memory for the Catalog. The raised exception will cause Katana to crash. If not set, Katana will continue to allocate memory (ignoring any soft limits set byKATANA_IMAGE_MEMORY
andKATANA_IMAGE_DISK_MEMORY
).KATANA_TMPDIR
Path to directory where Katana should store temporary files.
KATANA_KEEP_TMPDIR
If defined, Katana won’t clean the temporary directory on exit.
KATANA_KEEP_TEMP_RENDER_FILES
If defined, Katana won’t delete the temporary render files after a disk render.
KATANA_PERSISTENT_IMAGES_PATH
Directory where persistent images (like the ones from the catalog) should be stored.
KATANA_PERSISTENT_IMAGES_PREFIX
Filename prefix for persistent images to be used when they’re saved. The default is ‘default’.
KATANA_SPEC_CACHE_ENABLED
Lets the user enable or disable the render’s speculative caching. If defined, with a value greater than zero, it’s enabled; otherwise disabled. By default, it’s disabled only in Batch mode.
Enable or disable interframe caching of images. The interframe cache (that is, images generated for one render being used to help in another render) can make it difficult to debug some kinds of errors. By disabling the caching, you’re guaranteed a ‘clean’ render every time, but the rendering will be slower.
KATANA_PIPE_MAX_QUEUE_SIZE
If defined, controls the maximum size of the message queue used by renderer plug-ins to communicate with Katana’s catalog.
Alembic_In Options
KATANA_ALEMBICIN_DISABLE_MMAP
The Alembic_In node and associated Op uses an extended Alembic library to read Ogawa format Alembic files using memory-mapped I/O. This allows faster reads in general, and better multi-threaded performance with fewer locks.
If set to
1
ortrue
, this memory-mapped I/O extension is disabled and Alembic_In will revert to using file-streams to read Alembic files.
UsdIn Options
USD_ABC_XFORM_PRIM_COLLAPSE
This environment variable is relevant when using Alembic files inside USD. Set this to
0
if you don’t want transforms with a single geometry or camera in an Alembic file to be collapsed into a single prim in USD.USD_ABC_WRITE_UV_AS_ST_TEXCOORD2FARRAY
If set to
0
writing Alembic uv sets asprimvars:st
with typetexCoord2fArray
to USD. This affects how Alembic references are imported into Katana via UsdIn as well.USD_IMPORT_USD_LUX_LIGHTS_WITH_PRMAN_SHADERS
If set to
1
basic UsdLux prims will import with RenderMan light shader information as well. Off by default. RfK must also be setup in the environment.USD_KATANA_ADD_CUSTOM_PROPERTIES
If set to
0
UsdIn will not import custom properties set on Usd prims. Otherwise, and by default, custom attributes will be imported undercustomProperties
.USD_KATANA_ALLOW_CUSTOM_MATERIAL_SCOPES
If set to
0
, this will limit material assignments to materials scoped under a Looks prim.USD_KATANA_API_SCHEMAS_AS_GROUP_ATTR
If
1
, API schemas will be imported as group attributes instead of an array of strings. This provides easier support for CEL matching based on API schemas and an easier way to access the instance name of Multiple Apply Schemas.KATANA_USD_GLOBALS_TRAVERSE_MODEL_HIERARCHY
If set to
0
theUsdIn.UpdateGlobalLists
Op will traverse the entire USD stage, rather than just the prims part of the model hierarchy. This affectslightList
andglobals.cameraList
attribute creation on/root/world
. In both cases, theUsdLuxLightListAPI
can be used to store lightLists and control the cache behaviour for light lists.USD_KATANA_LOOK_TOKENS
This environment variable defines which prim names will allow for any child Material prims which have sibling materials to become child materials where a Specializes composition arc exists between them. The defaults are
Looks
,looks
andmaterials
, separated by the OS path separator.
Debugging
RUNTIME_OPTREE_GRAPH_DUMP
Path to a file used to dump the optree graph while rendering. This is useful for debug or inspection, especially when writing Ops.
KATANA_EVENT_DEBUG
When defined, causes all events in the EventModule to be printed out.
KATANA_RENDER_DEBUG
When defined with anything apart from
0
or''
causes 2D rendering to output additional log messages.KATANA_RENDER_INTERCEPT
The file system location path of an executable script or binary to be called instead of
renderboot
when starting a render. Receives the arguments thatrenderboot
normally receives.Debugging using a Debugger
KATANA_RENDER_INTERCEPT
is ideal for debugging therenderboot
process. Consider the following Linux shell script:#!/bin/bash exec xterm -e gdb --args "$KATANA_ROOT/bin/renderboot" "$@"
If
KATANA_RENDER_INTERCEPT
is set to the file system location path of thedebugging-interceptor.sh
script, renders started from Katana will be run throughgdb
. Note that the script invokesrenderboot
in the$KATANA_ROOT/bin/
directory, passing along all of the arguments it receives, but the render process is run as an inferior process from withingdb
, rather than directly.The
xterm
terminal emulator for X is used here in order to be able to interact withgdb
. Other terminal emulators with a similar-e
command-line option can be used instead.Debugging using a Profiler
Another usage of
KATANA_RENDER_INTERCEPT
is profiling. For instance, to run arenderboot
session through the Intel® VTune™ Profiler, the following script could be used:#!/bin/bash exec vtune -collect hotspots -knob sampling-mode=hw -knob sampling-interval=1 "$KATANA_ROOT/bin/renderboot" "$@"
Debugging using Environment Variables
The program specified by
KATANA_RENDER_INTERCEPT
can be used to alter the environment in whichrenderboot
is started. For example,PATH
orLD_LIBRARY_PATH
could be extended, orLD_PRELOAD
orLD_DEBUG
could be set.Important
The script or binary specified by
KATANA_RENDER_INTERCEPT
must have executable permissions, and its file system location must be accessible from the environment in which Katana is run.KATANA_INTERPROCESS_GC_TIMEOUT_SECONDS
A ZeroMQ keep alive message is sent periodically from the render side of the Display Driver, to instruct Katana not to clean up image data references. If the Katana Catalog Server does not receive a keep alive message within a specified timeout, it cleans up references to any image structures it may have been holding on to in order to receive image data for the Catalog. By default, this garbage collection process occurs every 30 minutes, but can be controlled by setting this environment variable.
KATANA_OPSCRIPT_INTERPRETER
Switches the Lua interpreter used by the OpScript node to either Lua 5.1 (if set to
Lua_5_1
) or LuaJIT 2.1 (if unset, or set toLuaJIT_2_1
). LuaJIT provides better performance.KATANA_OPSCRIPT_LUAJIT_JIT_COMPILER_ENABLED
Defines the default enable state of the JIT compiler of the LuaJIT interpreter used by the OpScript node. LuaJIT’s JIT compiler is disabled by default due to memory allocation-related performance issues that can arise under normal usage. Enable it by setting this variable to
1
.KATANA_PYTHONWARNINGS
Sets the handling for warnings from the
warnings
module. The value set is passed to asimplefilter
. See filter values from thewarnings
module for more information. Defaults todefault
.
Advanced
KATANA_ORIG_STDERR
(Read-only) when batch rendering, Katana currently captures both stdout and stderr and, ultimately, redirects them to the Python logging system, where a logging handler writes messages to the render log file as info messages. It is not currently possible to disable this redirection of standard streams. However, there is a way to access the original standard streams from plug-ins like Ops through the use of the environment variables
KATANA_ORIG_STDOUT
andKATANA_ORIG_STDERR
. Each variable contains the numeric file descriptor (Linux) or file handle (Windows) for the original stream.KATANA_ORIG_STDOUT
(Read-only) see above.
KATANA_DISABLE_UTF8
Katana sets Python’s default string encoding to UTF-8, unless this environment variable is defined.
KATANA_DISABLE_WORKING_SETS_UI
If defined, disables the working sets features for hiding or disabling the relative UI elements.
KATANA_DISABLE_MATERIALFILENAMERESOLVE
If set to
1
, disables Katana’s use of the MaterialFilenameResolve Op (in the Implicit Resolver Op chain, the MaterialResolve node’s Op chain, and in the SceneGraphView terminal Op chain).KATANA_DISABLE_RENDERERPROCEDURALFILENAMERESOLVE
If set to
1
, disables Katana’s use of the RendererProceduralFilenameResolve Op (in the Implicit Resolver Op chain, the MaterialResolve node’s Op chain, and in the SceneGraphView terminal Op chain).KATANA_VALUEPOLICY_MIMEDATA_ARRAY_SIZELIMIT
When copying or dragging a parameter or attribute representing an array of values, or a group containing such parameters or attributes, the corresponding MIME data of format
'policy/xml'
is clamped to a maximum of values for each array. This limit was introduced to avoid generating large amounts of XML text for very large arrays of values. This variable can be set to a numeric value to customize this limit (default: 16).