Service Start TOP node

Starts a PDG service.

Since

19.5

This node creates work items that will start up a PDG service.

Tip

You can also start up PDG services from the PDG Services panel.

Parameters ¶

Service Start ¶

Open PDG Service Panel

Opens the PDG Services panel.

Generate When

Determines when this node will generate work items. You should generally leave this set to “Automatic” unless you know the node requires a specific generation mode, or that the work items need to be generated dynamically.

All Upstream Items are Generated

This node will generate work items once all of the input nodes have generated their work items.

All Upstream Items are Cooked

This node will generate work items once all of the input nodes have cooked their work items.

Each Upstream Item is Cooked

This node will generate work items each time a work item in an input node is cooked.

Automatic

The generation mode is selected based on the generation mode of the input nodes. If any of the input nodes are generating work items when their inputs cook, this node will be set to Each Upstream Item is Cooked. Otherwise, it will be set to All Upstream Items are Generated.

Start Service During

Determines when the service is started.

Cook (In-Process)

Starts the service during the cook stage in the same process as the Houdini session.

Generate

Starts the service when the work item is generating.

Copy Inputs to Outputs

When on, work items in this node copy input files to their output file list.

Service Already Running

Determines how the node operates when the specified service (as defined by the Service Name parameter) is already running.

None

The node does nothing and the work item will successfully cook.

Report Warning

The node reports a warning and the work item will successfully cook.

Report Error

The node reports an error and the work item will fail.

Service Name

Specifies the name of the service to start. Type the name in this field or select the service from the drop-down list. If you want to start multiple services at once, then you can specify an expression.

Schedulers ¶

TOP Scheduler Override

This parameter overrides the TOP scheduler for this node.

Work Item Label

Determines how the node should label its work items. This parameter allows you to assign non-unique label strings to your work items which are then used to identify the work items in the attribute panel, task bar, and scheduler job names.

Use Default Label

The work items in this node will use the default label from the TOP network, or have no label if the default is unset.

Inherit From Upstream Item

The work items inherit their labels from their parent work items.

Custom Expression

The work item label is set to the Label Expression custom expression which is evaluated for each item.

Node Defines Label

The work item label is defined in the node’s internal logic.

Label Expression

When on, this parameter specifies a custom label for work items created by this node. The parameter can be an expression that includes references to work item attributes or built-in properties. For example, $OS: @pdg_frame will set the label of each work item based on its frame value.

Work Item Priority

This parameter determines how the current scheduler prioritizes the work items in this node.

Inherit From Upstream Item

The work items inherit their priority from their parent items. If a work item has no parent, its priority is set to 0.

Custom Expression

The work item priority is set to the value of Priority Expression.

Node Defines Priority

The work item priority is set based on the node’s own internal priority calculations.

This option is only available on the Python Processor TOP, ROP Fetch TOP, and ROP Output TOP nodes. These nodes define their own prioritization schemes that are implemented in their node logic.

Priority Expression

This parameter specifies an expression for work item priority. The expression is evaluated for each work item in the node.

This parameter is only available when Work Item Priority is set to Custom Expression.

See also

TOP nodes

Attribute Array

Creates and modifies array attributes on work items.
Attribute Copy

Copies attributes from work items in one branch onto work items in another branch.
Attribute Create

Creates or sets an attribute on all incoming work items.
Attribute Delete

Removes attributes from work items.
Attribute Dictionary

Modifies dictionary attributes by adding key/value pairs, removing keys, or merging existing dictionaries
Attribute Promote

Copies attributes and fields between work items, global attributes, and output files
Attribute Randomize

Create randomly-generated integer and float attributes on work items.
Attribute Reduce

Reduces array attribute values to a single value.
Attribute Rename

Renames attributes on work items.
Attribute from File

Parses attribute values from a file into work items.
Attribute from String

Parses attribute values from a string, such as a file name.
Block Begin Feedback

Starts a feedback loop. TOP nodes within the block execute serially, optionally looping for each incoming work item.
Block End Feedback

Ends a feedback loop. TOP nodes within the block execute serially, optionally looping for each incoming work item.
CSV Input

Copies data from a CSV file into work item attributes.
CSV Output

Writes work item attributes to a CSV file.
Deadline Scheduler

The PDG scheduler for Thinkbox’s Deadline software.
Download File

Downloads the contents from one or more URLs into files.
Environment Edit

Edits the variables set in the environment work item command lines execute in.
Error

Issues warnings or errors when a condition is met.
FFmpeg Encode Video

Encodes a sequence of still images as a video file.
FFmpeg Extract Images

Extracts a sequence of still images from a video file.
File Compress

Compress files into an archive.
File Copy

Copies a file from one location to another, either at runtime or whenever the node generates.
File Decompress

Decompresses archive files specified by incoming work items into individual files.
File Pattern

Creates work items based on files that match a certain pattern.
File Range

Creates a range of work items based on files that match a certain pattern.
File Remove

Deletes a file at a specified path.
File Rename

Renames or moves a file.
Filter by Attribute

Filters upstream work items by their attribute names or values
Filter by Expression

Conditionally filters upstream work items.
Filter by Range

Filter upstream work items that fall within a specified frame or attribute range.
Filter by State

Filters upstream work items by their state
Generic Generator

Generates work items with no attributes that run a command line.
Geometry Import

Loads points or primitives from a SOP or geometry file into work item attributes or a temporary file.
HDA Processor

Creates work items that cook a digital asset
HQueue Scheduler

Schedules work items using HQueue.
Houdini Block Begin

Starts a Houdini service block
ImageMagick

Provides easy access to ImageMagick functionality such as mass image convert, resize, and image mosaics.
In Process Scheduler

Controls the scheduling of in-process work items.
Invoke

Invokes a compiled block on input geometry
JSON Input

Extracts data from JSON files and creates attributes
JSON Output

Performs various operations that produce JSON output
Labs Archive Project

Utility TOP to Collect and Archive current HIP file dependencies
Labs Concatenate Text

Merges one or more text files into a single file.
Labs Cut Geometry to Partitions

Cuts up incoming geometry
Labs Data Diff

Diffs a variety of geometry, text and image files.
Labs Extract Image Metadata

Extracts image metadata, such as the resolution, bit depth, color model, etc.
Labs File Cache Filter

Partition work items used for file caching
Labs File Cache Partitioner

Partitions and generates work items based on range and wedge values for file cache.
Labs Filter by Value

Filters one or multiple work items by specific attribute values.
Labs Generate from Imageplanes

Generates work items based on image planes found in an image
Local Scheduler

Schedules work items on the local machine.
ML Regression Train

Trains a neural network for regression.
Make Directory
Maya Block Begin

Starts a Maya service block
Merge

Merge all upstream work items
Node Pattern

Creates work items based on matched nodes.
Nuke Block Begin

Starts a Nuke service block
Null

Does nothing
OP Notify

Notify an OP node that some TOP work has completed
OpenImageIO

Provides easy access to the OpenImageIO’s command line tool, also known as oiiotool, to perform operations on images such as color space conversion, color mapping, resizing, text overlay, and box overlay.
Output

Subnet output
Partition by Attribute

Partitions work items based on their attributes
Partition by Bounds

Partitions source items spatially using the bounding items.
Partition by Combination

Partitions work items into pairs, triples, etc
Partition by Comparison

Partitions work items using existing comparisons
Partition by Expression

Partitions work items based on an expression
Partition by Frame

Partitions work items based on their frame
Partition by Index

Partitions work items based on their index
Partition by Iteration

Partitions work items based on their feedback loop iteration.
Partition by Node

Partitions work items based on their node
Partition by Range

Partition work items based on range values
Partition by Tile

Partitions work items spatially using axis-aligned bounding boxes.
Perforce

Execute Perforce commands through PDG
Python Block Begin

Starts a Python service block
Python Partitioner

Partitions work items using a Python script
Python Processor

Generates work items using a Python script.
Python Scheduler

A Python-based programmable Scheduler for PDG.
Python Script

Creates work items that run a Python script.
Python Virtual Environment

Creates a Python virtual environment using TOPs
ROP Alembic Output

Creates work items that cook an embedded Alembic ROP node
ROP Composite Output

Creates work items that cook an embedded Composite ROP node
ROP FBX Output

Creates work items that cook an embedded FBX ROP node
ROP Fetch

Creates work items that cook a ROP node or network.
ROP Geometry Output

Creates work items that cook an embedded Geometry ROP node
ROP Image Output

Creates work items that cook an embedded Image ROP node
ROP Karma Render

Creates work items that cook an embedded Karma ROP node.
ROP Mantra Render

Creates work items that cook an embedded Mantra ROP node
ROP OpenGL Render

Creates work items that cook an embedded OpenGL ROP node
ROP USD Output

Creates work items that cook an embedded USD ROP node
Range Extend

Extend the frame range of upstream work items and adds new work items as necessary
Range Generate

Generates work items for the specified range.
Remote Graph

Connected to a remotely executing TOP graph and displays the nodes from that graph
Render IFD

Creates work items that render an IFD file with Mantra
SQL Input
SQL Output
Send Email

Sends an email.
Service Block End

Ends a service block.
Service Block Send

Sends code to a service block to execute.
Service Create

Creates a PDG service.
Service Delete

Deletes a PDG service.
Service Reset

Resets a PDG service.
Service Start

Starts a PDG service.
Service Stop

Stops a PDG service.
ShotGrid Create

Creates ShotGrid entities
ShotGrid Delete

Deletes entities from ShotGrid
ShotGrid Download

Downloads ShotGrid attachments
ShotGrid Find

Finds ShotGrid entities
ShotGrid Server Begin

Starts a persistent ShotGrid command server
Shotgun Update

Updates shotgun entities
Shotgun Upload

Uploads files to shotgun
Sort

Sorts work items by a list of attributes
Split

Splits upstream items in two
Split by Count

Splits upstream items into two using a fixed count
Subnetwork

Container for TOP nodes
Switch

Switch which between network branches
TOP Fetch

Cooks another TOP network.
TOP Fetch Input

Input to a TOP fetch-ed network
Text Output

Writes text to a new file or appends to an existing file.
Tractor Scheduler

Schedules work items using Pixar’s Tractor.
Train OIDN

Trains an OIDN model using preprocessed training and validation datasets.
URL Request

Creates work items that request data from a URL.
USD Add Assets to Gallery

Adds USD assets to the Asset Gallery.
USD Analyze

Fetches metadata, dependencies, and external references for a LOP Node or file.
USD Import Data

Creates work items from prims found in a USD stage.
USD Import Files

Creates work items from file references found in a USD stage.
USD Modify Paths

Modify asset path attribute values.
USD Render Files

Creates work items that render a USD file.
USD Render Scene

Creates work items that render a USD file or LOP network
Wait for All

Waits for all upstream work items to complete.
Wedge

Creates work items with varying attribute values.
Work Item Expand

Expands file lists or partitions into multiple work items
Work Item Import

Import work items from a .json file or another TOP node.
Xml Input

Extracts data from XML into Work Item attributes