Determine the progress of compaction tasks that have
children.
The progress of a compaction task is calculated using the default
get_progress method. If the expected_total_workload method is
implemented, the default progress is computed as:
(sum of child task progresses) / (expected total workload)
If expected_total_workload is not defined, progress is estimated based
on children progresses. However, in this case, the total progress may
increase over time as the task executes.
All compaction tasks, except for reshape tasks, implement the
expected_children_number method. To compute expected_total_workload,
iterate over all SSTables covered by the task and sum their sizes. Note
that expected_total_workload is just an approximation and the real workload
may differ if SStables set for the keyspace/table/compaction group changes.
Reshape tasks are an exception, as their scope is determined during
execution. Hence, for these tasks expected_total_workload isn't defined
and their progress (both total and completed) is determined based
on currently created children.
Fixes: https://github.com/scylladb/scylladb/issues/8392.
Fixes: https://github.com/scylladb/scylladb/issues/6406.
Fixes: https://github.com/scylladb/scylladb/issues/7845.
New feature, no backport needed
Closesscylladb/scylladb#15158
* github.com:scylladb/scylladb:
test: add compaction task progress test
compaction: set progress unit for compaction tasks
compaction: find expected workload for reshard tasks
compaction: find expected workload for global cleanup compaction tasks
compaction: find expected workload for global major compaction tasks
compaction: find expected workload for keyspace compaction tasks
compaction: find expected workload for shard compaction tasks
compaction: find expected workload for table compaction tasks
compaction: return empty progress when compaction_size isn't set
compaction: update compaction_data::compaction_size at once
tasks: do not check expected workload for done task
6116f9e11b