mirror of https://github.com/citusdata/citus.git
00a94c7f13
DESCRIPTION: Add infrastructure to run long running management operations in background This infrastructure introduces the primitives of jobs and tasks. A task consists of a sql statement and an owner. Tasks belong to a Job and can depend on other tasks from the same job. When there are either runnable or running tasks we would like to make sure a bacgrkound task queue monitor process is running. A Task could be in running state while there is actually no monitor present due to a database restart or failover. Once the monitor starts it will reset any running task to its runnable state. To make sure only one background task queue monitor is ever running at once it will acquire an advisory lock that self conflicts. Once a task is done it will find all tasks depending on this task. After checking that the task doesn't have unmet dependencies it will transition the task from blocked to runnable state for the task to be picked up on a subsequent task start. Currently only one task can be running at a time. This can be improved upon in later releases without changes to the higher level API. The initial goal for this background tasks is to allow a rebalance to run in the background. This will be implemented in a subsequent PR. |
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| .. | ||
| 11.1-1.sql | ||
| latest.sql | ||