[serve] Stop scheduling task early when requests have been cancelled #47847
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Signed-off-by: Cindy Zhang <[email protected]>
edoakes
approved these changes
Oct 4, 2024
| @@ -744,6 +743,18 @@ async def fulfill_pending_requests(self): | |||
| ) | |||
| logger.warning(warning_log) | |||
|
|
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| # Clear out pending requests at the front of the | |||
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It's a minor optimization, but should this be at the top of the loop instead? The problematic situation could occur immediately after choose_two_replicas_with_backoff
Signed-off-by: Cindy Zhang <[email protected]>
Signed-off-by: Cindy Zhang <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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Oct 15, 2024
…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
ujjawal-khare
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
ujjawal-khare
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
ujjawal-khare
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
ujjawal-khare
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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…ay-project#47847) In `fulfill_pending_requests`, there are two nested loops: - the outer loop greedily fulfills more requests so that if backoff doesn't occur, it's not necessary for new asyncio tasks to be started to fulfill each request - the inner loop handles backoff if replicas can't be found to fulfill the next request The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary. This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in `pending_requests_to_fulfill` that have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests. Tests: - Added a test that tests for the scenario where a request is cancelled while it's trying to find an available replica - Also modified the tests in `test_pow_2_scheduler.py` so that the backoff sequence is small values (1ms), and the timeouts in the tests are also low `10ms`, so that the unit tests run much faster (~5s now compared to ~30s before). ## Related issue number related: ray-project#47585 --------- Signed-off-by: Cindy Zhang <[email protected]> Signed-off-by: ujjawal-khare <[email protected]>
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Why are these changes needed?
In
fulfill_pending_requests, there are two nested loops:The outer loop will be stopped if there are enough tasks to handle all pending requests. However if all replicas are at max capacity, it's possible for the inner loop to continue to loop even when the task is no longer needed (e.g. when a request has been cancelled), because the inner loop simply continues to try to find an available replica without checking if the current task is even necessary.
This PR makes sure that at the end of each iteration of the inner loop, it clears out requests in
pending_requests_to_fulfillthat have been cancelled, and then breaks out of the loop if there are enough tasks to handle the remaining requests.Tests:
test_pow_2_scheduler.pyso that the backoff sequence is small values (1ms), and the timeouts in the tests are also low10ms, so that the unit tests run much faster (~5s now compared to ~30s before).Related issue number
related: #47585
Checks
git commit -s) in this PR.scripts/format.shto lint the changes in this PR.method in Tune, I've added it in
doc/source/tune/api/under thecorresponding
.rstfile.