explain why finalizers are not processed in order #83110
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| // Finalizers may be processed and removed in any order. Order is NOT enforced | ||
| // because it introduces significant risk of stuck finalizers. | ||
| // finalizers is a shared field, any actor with permission can reorder it. | ||
| // If the finalizer list is processed in order, then this can deadlock finalizers. |
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"then this can deadlock finalizers" makes it sound like a bug in the API server. Maybe rephrase like "this can lead to a situation in which the component responsible for the first finalizer in the list is waiting for a condition produced by a component responsible for a finalizer later in the list, resulting in a deadlock."
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| // Finalizers may be processed and removed in any order. Order is NOT enforced | ||
| // because it introduces significant risk of stuck finalizers. | ||
| // finalizers is a shared field, any actor with permission can reorder it. | ||
| // If the finalizer list is processed in order, then this can lead to a situation |
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Carrying on from the previous sentence, consider starting this one to clarify:
Since the finalizer order is difficult to coordinate, processing the finalizer list in order could lead to a situation in which the component responsible for the first finalizer in the list would be waiting for a signal (such as a particular field value to change or an external system to perform some operation) produced by a component responsible for a finalizer later in the list, resulting in a deadlock.
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This came up in slack and appeared frequent enough to deserve a note for future us.
@kubernetes/sig-api-machinery-misc