Queue Control

Consider that you want to offload your highest-processing jobs to FME Engines that are installed on a separate server, named "FMEServer2". On the Workspaces page, inside individual repositories, you can see some useful performance statistics for workspaces that have run jobs to date, or since the statistics were updated. You decide to offload jobs to this server based on a combination of Average % CPU > 80 and Average CPU Time > 1 Hour.

First, you create a separate queue, named queue_FMEServer2, that will hold the jobs that are routed to the engines on FMEServer2.

Next, you create a job routing rule that specifies: 1) Your job routing criteria—in this case, %CPU > 80 % AND CPU Time > 1 Hour; and 2) Jobs that meet these criteria are assigned to queue_FMEServer2. (Note that you can assign a job routing rule to only one queue. A queue, however, can be assigned to multiple job routing rules.)

Finally, you create an engine assignment rule that specifies which engines run jobs that are routed to queue_FMEServer2. You can specify the engines by name. However, a better option is to specify the engines based on a common system property assigned to all the engines installed on server FMEServer2. On the Engines tab, you can see that one of the system properties assigned to your FME Engines is the server name on which they are installed. In this case, some of your engines are assigned the property FMEServer2. This way, if you add more engines to FMEServer2, they can also run jobs in the queue without explicitly adding them to this rule. (Note that more than one queue can be assigned to an engine assignment rule.)

1. Queues Tab: Create a Queue

1. On the Queues tab, click New.
2. Enter a Name and Description (optional) for the queue.
3. Assign a Priority (defaults to 5). Priority must be an integer between 1 and 10. The highest priority is 1 and the lowest priority is 10. Queues with higher priority submit job requests before queues with lower priority, depending on timing.
4. Click OK.

2. Job Routing Rules Tab: Assign the Queue to a Rule

To assign a queue to an existing rule:

1. Open the Job Routing Rules tab and click on a rule to open it.
2. In the Queue field, update the queue to which this rule applies.
3. Click OK.

Note: You can assign a rule to only one queue.

To assign a queue to a new rule:

1. Open the Job Routing Rules tab and click New.
2. On the Create Job Routing Rule page, specify the following:
   • A Name for the rule.
   • Type:
     • Metric: The queue handles jobs that meet the requirements of specified job performance measures, including one or more of the following:
       • % CPU: Jobs whose Average % CPU meets the requirements specified in the rule.
       • CPU Time: Jobs whose Average CPU Time meets the requirements specified in the rule.
       • Elapsed Time: Jobs whose Average Elapsed Time meets the requirements specified in the rule.
       • Peak Memory Usage: Jobs whose Average Peak Memory Usage meets the requirements specified in the rule.

       Using boolean logic, specify the parameters of the Rule. To add parameters to the rule, click + Rule. To nest parameters in the rule, click + Ruleset.

       For example, for a combination of Average % CPU > 80 and Average CPU Time > 1 hour, specify % CPU > 80 % AND CPU Time > 1 Hour.

     Note: For a metric-based job routing rule to take effect, the workspace must have run enough times since statistics are initially collected or reset to generate a statistically significant sample. The required minimum number of jobs to run for a significant sample may vary between 30 to 100, depending on variability of data and the degree of precision required by the rule (for example, minutes versus seconds). The more variable the input data, and the higher degree of precision that is required of this data, the larger the sample size that is required. If a job routing rule does not reference a statistically significant sample of jobs run, the next applicable rule takes effect, by priority, or the job routes to the Default queue.

     • Repository: The queue handles jobs in one ore more specified repositories.
       • Repositories: Specify one or more repositories to apply to the queue.
   • Queue: Apply this rule to a queue.
   • Enabled: By default, the rule is enabled, which means that subsequent jobs that meet the requirements of the rule are routed to the specified Queue. If disabled, jobs that would otherwise route to this queue based on this rule instead route to the next applicable rule, by priority (see Prioritizing Job Routing Rules, below). If no other rules apply, jobs route to the Default queue.
3. Click OK.

3. Engine Assignment Rules Tab: Specify How Engines are Assigned to Queues

A set of engine assignment rules determines how engines are assigned to queues. You can assign queues to specific engines by name, or based on the properties an engine holds.

To add a queue to an existing engine assignment rule:

1. Open the Engine Assignment Rules tab.
2. Click the rule to which you want to add the queue.
3. On the Editing Engine Assignment Rule page, add the queue to the Queues field.
4. Click OK.

To add a queue to a new rule

1. Open the Engine Assignment Rules tab, and click New.
2. On the Create Engine Assignment Rule page, specify:
   • A Name for the rule.
   • Type:
     • Property: Engines are assigned to queues based on properties that are defined on engines.
       • Rule: Using boolean logic, specify how the properties that are defined on engines determine if they are assigned to the specified queue(s).

        To add an engine property to a rule:

       1. click Add Property.
       2. On the Create Engine Property dialog, enter the property as it appears on the Engines tab, and click OK.

       Note:  

       Engine properties do not auto-populate in the Create Engine Property dialog. You must enter property names as they appear on the Engines tab.

       For Kubernetes deployments of FME Engines, specify the name property of the applicable engine deployment. For more information, see Defining FME Engines and Queue Control Properties to a Kubernetes Deployment.

       3. Click + Rule. A new drop-down is added to the rule.
       4. In the new drop-down, select the newly-added property.

       To nest properties in the rule, click + Ruleset.

       For example, to specify any dynamic engine on server Whistler, specify DYNAMIC AND WHISTLER.

     • Name: Engines are assigned to queues by engine name.
       • Engines: Specify the engine names you want to assign to the queue(s).

       Note: You cannot specify any engines that are assigned to Streams.

   • Queues: Specify one or more queues to route jobs to the engines specified in this rule.
   • Enabled: By default, the rule is enabled. If disabled, jobs that would otherwise route to engines based on this rule instead route to the Default queue.
3. Click OK.