Using Queues
Groups of processes are managed using queues. Queues distribute processes to process servers, where the processes actually run.
You can use queues to limit the number of processes that can run simultaneously, distribute workload across multiple systems and provide fail-over facilities. One queue can be attached to multiple process servers, in which case Redwood Server decides which process server to run the processes at when the process starts. One process server can be attached to multiple queues, in which case it can run processes from any of those queues.
- Creating a Queue.
- Using Queues to Administer Process Execution.
- Using Resources to distribute the load.
- Controlling Queues with RedwoodScript.
note
Redwood recommends you to specify a time zone on a queue, especially when you tie a time window to it to ensure the correct time is used.
Finding Queues
You can search for queues using filters and the Search Queues box on the Queues tab. This box is known as the IntelliSearch box and located under your username on the top right-hand side of the user interface. Filters allow you to specify a list of objects with static criteria. IntelliSearch allows you to specify complex queries in a simple way using prefixes. Prefixes are used to specify which property you are searching in and have short as well as long syntaxes. For example, if you want to display all queues with the term production in the comment, you would use the search criteria as follows:
c:production
You can search more than one property, as follows:
c:production n:B1I
note
No spaces should be entered before or after the colon (: ).
See the Advanced Object Search for more information.
The following table illustrates the available prefixes for queues:
| Prefixes | Description |
|---|---|
| n, name | searches the name property |
| c, comm, comment | searches the documentation property |
| d, desc, description | searches the description property |
| a, application | searches the application property |
| cb, changedbefore | (internal) search for queues that changed before a certain ISO-8601 period |
Deleting Queues
You can only delete queues when no other objects relate to them. For example, if there are processes that have run in the queue, the queue cannot be deleted until all processes that ran in it have been deleted. You can see all processes that relate to the queue in Related Objects in the lower detail pane and on the show page.
The table in related objects contains three columns:
- Type - the type of object with a link to it
- Related Object - the name of the object with a link to it
- Used As - objects can sometimes be used in different roles