Limits and Machine Limits

Overview

Limits are used to restrict access to a certain resource that can be shared by multiple jobs.

For example, it’s not uncommon for a render farm to have more render nodes than floating licenses for a specific rendering application or plugin. In this situation, contention for floating licenses can lead to license errors when those floating licenses have been exhausted, and these license errors can lead to wasted render time and reduced productivity. License Limits can be used to in this case to restrict access to a particular floating license.

Another example is shared data on a file server. Many Jobs could require access to the same data, like textures, particle caches, etc, which normally isn’t an issue (since they’re on a file server). However, perhaps the file server isn’t capable of serving that data to a large number of render nodes simultaneously, or perhaps the network doesn’t have the bandwidth to transfer that much data at once. This situation can lead to file server or network instability, which can lead to increased render times or errors. Resource Limits can be used in this case to restrict access to non-license resource.

Machine Limits function similarly, but are on a per-Job basis. Instead of limiting how many Slaves can render a group of Jobs, they limit the number of Slaves that can render one particular Job. This is useful if you want to prevent a job from potentially taking up the entire farm.

Finally, plugin Limits ensure 1 or more Limits are always applied to a certain application plugin, no matter how many Jobs are being processed.

Job Machine Limits

Machine Limits are a per-Job option, and can be managed through the Job’s Properties window, which you can get to by right-clicking on the Job and selecting ‘Modify Job Properties’. More information on the available Machine Limit settings can be found in the Controlling Jobs documentation.

../_images/jp_machine_limit.png

Plugin Limits

Plugin Limits are a per-Plugin (application) option, and can be managed through Configure Plugins… under Tools when in Super User mode. Plugin level limits via the Set Limits button allows you to assign one or more limits to always be applied to a certain application plugin. This ensures that limit is applied to all jobs that process using that specific plugin in your farm.

../_images/limit_plugin.png

Limits

Deadline 10 introduces the concept of Limit types, and there are two types:

  • License Limits: These are used to restrict access to floating licenses, which helps avoid errors when those licenses are exhausted. They also enable 3rd Party Usage Based Licensing (UBL).
  • Resource Limits: These are used to restrict access to non-license resources, such as large data caches.

Jobs (or plugins) can be configured to require one or more Limits, and a Slave will only render a job if it is able to acquire a ‘Stub’ for each Limit. Every Stub that is aquired for a Limit counts against that Limit’s usage. For example, if a Limit has a maximum of 10, and 8 Stubs have been acquired by different Slaves, then only 2 more Stubs are available. If all the Stubs for a Limit have been acquired, then no more Slaves will be able to pick up jobs that require that Limit. When a Slave finishes a job, it returns any unused Stubs so that other Slaves can acquire them.

Both types of Limits can be managed from the Limits panel in the Monitor while in Super User mode (or as a user with appropriate User Group privileges). This list shows all the Limits that are in your Repository. It also displays useful information about each Limit, such as its Name, Status, Limit Type, and the number of Limit Stubs that are currently in use.

Note

Limit types were introduced in Deadline 10.0.9. If you’re upgrading from an earlier version of Deadline 10, any existing Limits will have their type assigned automatically, and will function as normal. There is no need to edit them.

By default, the Limits panel will show both types of Limits, and you can use the Limit Type quick filter to filter out one of the types if you wish. Simply toggle on the Quick Filter button in the top left corner of the Limits panel, and select the Limit Type that you want to see in the Quick Filter panel that appears on the left.

../_images/limits_right_click.png

You can access many options for the Limits by right-clicking on them, and you can create a new License or Resource Limit by clicking on the [+] button in the top left corder of the Limits panel. If the Limits panel is not visible, see the Panel Features documentation for instructions on how to create new panels in the Monitor.

../_images/limits_create_new_limit1.png

New License Limit

Use this option to add a new License Limit to your Repository. This is also accessible using the shortcut Ctrl + N.

../_images/limits_create_new_license_limit1.png

You can modify the following settings for the new License Limit:

License Name

The name of the new License Limit. Note that this setting cannot be changed once the Limit has been created.

Usage Level

The level at which a Limit Count will be checked out. ‘Slave’ is the default, and will require each Slave to acquire a Stub; if ‘Machine’ is selected, only a single Stub will be required for all Slaves on the same machine. Conversely, if ‘Task’ is selected, Slaves will try to acquire one Stub per concurrent Render Thread. Note that this setting cannot be changed after Limit creation.

Enable Existing Licenses Usage

This option should be enabled if you are using this Limit to manage floating/network licenses. If you are only using this Limit for 3rd Party UBL, you can leave this disabled.

  • Unlimited Licenses: If you happen to have unlimited floating/network licenses, you can enable this option, and there will be no restriction on the number of Stubs that can be acquired for this Limit. This isn’t the typical use case though, and if this option is enabled, you can’t use 3rd Party UBL because it only activates when the existing license threshold has been reached.
  • License Count: If you have a finite amount of floating/network licenses (which is the typical use case), this is the number of licenses you have. If you are also using 3rd Party UBL, it will activate when these existing licenses have been exhausted.

Use Usage Based Licensing

This option should be enabled if you are using 3rd Party Usage Based Licensing. If this is used in combination with Existing Licenses, it will only activate when those existing licenses have been exhausted (which means you can’t use the Unlimited Licenses option). If this option is used on its own, then any Slave that acquires a Stub for this Limit will consume 3rd Party UBL.

  • UBL Application: This is the application that 3rd Party UBL is being used for (one application per Limit). If you are using 3rd Party UBL with multiple applications, you will need to create a Limit for each application.
  • Unlimited UBL: Use this option if you don’t want to restrict the number of Slaves that can use 3rd Party UBL. This can be useful if the Slave count for your farm fluctuates, and you want to ensure that all Slaves can use 3rd Party UBL.
  • UBL Count: Use this option if you want to restrict the number of Slaves that can use 3rd Party UBL. This can be useful if you want to keep costs down.

Whitelisted/Blacklisted Slaves

If Slaves are on a Blacklist, they will never try to render Jobs associated with this Limit. If Slaves are on a Whitelist, then they are the only ones that will try to render Jobs associated with this Limit. Note that an empty blacklist and an empty whitelist are functionally equivalent, and have no impact on which machines the job renders on.

Slaves Excluded From Limit

These Slaves will ignore this Limit and won’t contribute to the Limit Count. This is useful if you are juggling a mix of floating and node-locked licenses, in which case your machines with node-locked licenses should be placed on this list.

New Resource Limit

Use this option to add a new Resource Limit to your Repository. This is also accessible using the shortcut Ctrl + E.

../_images/limits_create_new_resouce_limit.png

You can modify the following settings for the new Resource Limit:

Resource Name

The name of the new Resource Limit. Note that this setting cannot be changed once the Limit has been created.

Usage Level

The level at which a Resource Count will be checked out. ‘Slave’ is the default, and will require each Slave to acquire a Stub; if ‘Machine’ is selected, only a single Stub will be required for all Slaves on the same machine. Conversely, if ‘Task’ is selected, Slaves will try to acquire one Stub per concurrent Render Thread. Note that this setting cannot be changed after Limit creation.

Unlimited Resources

If selected, then the Resource Limit can be used by an unlimited number of Slaves. Setting this will ignore the Resource Count value.

Resource Count

The maximum number of simultaneous uses (Stubs) that this Resource Limit can support at any given time. What counts as a ‘use/Stub’ is based on the Usage Level set above. Setting the Resource Count to 0 will result in no Jobs being rendered that require this Limit, but this can be useful if you want to temporarily disable a Limit without deleting it.

Release at Task Progress

If enabled, Slaves will release their Resource Limit stub when the current Task reaches the specified percentage. Note that support for Task progress depends on the plugin that the Job uses for rendering, and not all plugins support Task progress.

Whitelisted/Blacklisted Slaves

If Slaves (or Machines, depending on Level selected above) are on a Blacklist, they will never try to render Jobs associated with this Limit. If Slaves/Machines are on a Whitelist, then they are the only ones that will try to render Jobs associated with this Limit. Note that an empty blacklist and an empty whitelist are functionally equivalent, and have no impact on which machines the Job renders on.

Slaves Excluded From Limit

These Slaves (or Machines, depending on Level selected above) will ignore this resource Limit and won’t contribute to the Resource Count.

Clone Limit

This option allows you to create a new Limit while using an existing Limit as a template. It will bring up a dialog interface associated to the type of the selected limit, that is very similar to the one pictured in Create New Limit section, with all the same options. This option is handy if you want to create a Limit that is very similar to an existing one but with a small variation.

Modify Limit Properties

This option allows you to edit the settings for an existing Limit. All of the settings described in both New Limit sections above can be changed except for the Limit’s Name and Usage Level, which cannot be changed once the Limit has been created.

Reset Limit Usage Count

Sometimes a Limit Stub will get orphaned, meaning that it is counting against the Limit’s usage count, but no machines are actually using it. After a while, Deadline will eventually clean up these orphaned Limit Stubs. This option provides the means to delete all existing Stubs immediately (whether they are orphaned or not), which will require Slaves to acquire them again.

Delete Limit

Removes an existing Limit from your Repository. Any Jobs associated with deleted Limits will still be able to render, but they will print out Warnings indicating that the Limit no longer exists.

Limits and Job Scheduling

Although Limits and Job Machine Limits aren’t priority-based like Pools, they do have an impact on job scheduling. Here are some examples.

Limits

  • If a job is assigned to a Limit, and that Limit is currently maxed out, the job will not be picked up by any additional Slaves.
  • If a job is assigned to a Limit, and that Limit has a whitelist, the job will only render on the Slaves in that whitelist.
  • If a job is assigned to two Limits, and one of those Limits is currently maxed out, the job will not be picked up by any additional Slaves. This is because a Slave must be able to acquire all Limits that the job requires.
  • If a job is assigned to two Limits, and one of those Limits has slave_1 on its blacklist, slave_1 will never pick up the job. This is because a Slave must be able to acquire all Limits that the job requires.

Job Machine Limits

  • If a job has a Machine Limit greater than 0, and that Limit is currently maxed out, the job will not be picked up by any additional Slaves.
  • If a job has a whitelist, the job will only render on the Slaves in that whitelist.