Asynchronous prefetching of data

[MaxiBoether]

In order to hide the latency of data transfer from selector during training, we add an configurable number of partitions to be prefetched in the dataloader. Furthermore, we change the storage and selector to use processes instead of threads for serving gRPC requests.

Solves #175.

[github-actions]

✅ Result of Pytest Coverage

---------- coverage: platform linux, python 3.11.6-final-0 -----------

Name	Stmts	Miss	Cover
modyn/common/benchmark/stopwatch.py	26	0	100%
modyn/common/ftp/ftp_server.py	31	18	42%
modyn/common/ftp/ftp_utils.py	43	31	28%
modyn/common/grpc/grpc_helpers.py	67	36	46%
modyn/common/trigger_sample/trigger_sample_storage.py	74	4	95%
modyn/database/abstract_database_connection.py	35	0	100%
modyn/database/partition_by_meta.py	33	12	64%
modyn/evaluator/evaluator.py	25	1	96%
modyn/evaluator/evaluator_entrypoint.py	32	3	91%
modyn/evaluator/internal/dataset/evaluation_dataset.py	68	3	96%
modyn/evaluator/internal/grpc/evaluator_grpc_server.py	22	0	100%
modyn/evaluator/internal/grpc/evaluator_grpc_servicer.py	154	14	91%
modyn/evaluator/internal/metric_factory.py	18	1	94%
modyn/evaluator/internal/metrics/abstract_decomposable_metric.py	10	1	90%
modyn/evaluator/internal/metrics/abstract_evaluation_metric.py	29	2	93%
modyn/evaluator/internal/metrics/abstract_holistic_metric.py	10	1	90%
modyn/evaluator/internal/metrics/accuracy.py	20	2	90%
modyn/evaluator/internal/metrics/f1_score.py	65	0	100%
modyn/evaluator/internal/metrics/roc_auc.py	36	1	97%
modyn/evaluator/internal/pytorch_evaluator.py	107	21	80%
modyn/evaluator/internal/utils/evaluation_info.py	26	0	100%
modyn/evaluator/internal/utils/evaluation_process_info.py	8	0	100%
modyn/evaluator/internal/utils/evaluator_messages.py	3	0	100%
modyn/metadata_database/metadata_base.py	3	0	100%
modyn/metadata_database/metadata_database_connection.py	44	3	93%
modyn/metadata_database/models/pipelines.py	10	1	90%
modyn/metadata_database/models/sample_training_metadata.py	15	0	100%
modyn/metadata_database/models/selector_state_metadata.py	46	10	78%
modyn/metadata_database/models/trained_models.py	14	0	100%
modyn/metadata_database/models/trigger_partitions.py	10	0	100%
modyn/metadata_database/models/trigger_training_metadata.py	14	0	100%
modyn/metadata_database/models/triggers.py	10	0	100%
modyn/metadata_processor/internal/grpc/metadata_processor_grpc_servicer.py	18	0	100%
modyn/metadata_processor/internal/grpc/metadata_processor_server.py	24	0	100%
modyn/metadata_processor/internal/metadata_processor_manager.py	23	4	83%
modyn/metadata_processor/metadata_processor.py	11	0	100%
modyn/metadata_processor/metadata_processor_entrypoint.py	24	1	96%
modyn/metadata_processor/processor_strategies/abstract_processor_strategy.py	29	0	100%
modyn/metadata_processor/processor_strategies/basic_processor_strategy.py	17	2	88%
modyn/metadata_processor/processor_strategies/processor_strategy_type.py	6	1	83%
modyn/model_storage/internal/grpc/grpc_server.py	22	0	100%
modyn/model_storage/internal/grpc/model_storage_grpc_servicer.py	65	4	94%
modyn/model_storage/model_storage.py	24	5	79%
modyn/model_storage/model_storage_entrypoint.py	32	3	91%
modyn/models/articlenet/articlenet.py	30	16	47%
modyn/models/coreset_methods_support.py	29	1	97%
modyn/models/dlrm/cuda_ext/dot_based_interact.py	24	13	46%
modyn/models/dlrm/dlrm.py	67	9	87%
modyn/models/dlrm/nn/embeddings.py	123	64	48%
modyn/models/dlrm/nn/factories.py	24	9	62%
modyn/models/dlrm/nn/interactions.py	50	11	78%
modyn/models/dlrm/nn/mlps.py	77	23	70%
modyn/models/dlrm/nn/parts.py	60	4	93%
modyn/models/dlrm/setup.py	5	5	0%
modyn/models/dlrm/utils/install_lib.py	11	7	36%
modyn/models/dlrm/utils/utils.py	28	0	100%
modyn/models/fmownet/fmownet.py	25	0	100%
modyn/models/resnet18/resnet18.py	28	0	100%
modyn/models/tokenizers/distill_bert_tokenizer.py	11	0	100%
modyn/models/yearbooknet/yearbooknet.py	23	0	100%
modyn/selector/internal/grpc/selector_grpc_servicer.py	83	22	73%
modyn/selector/internal/grpc/selector_server.py	25	8	68%
modyn/selector/internal/selector_manager.py	135	43	68%
modyn/selector/internal/selector_strategies/abstract_selection_strategy.py	196	21	89%
modyn/selector/internal/selector_strategies/coreset_strategy.py	56	5	91%
modyn/selector/internal/selector_strategies/downsampling_strategies/abstract_downsampling_strategy.py	32	2	94%
modyn/selector/internal/selector_strategies/downsampling_strategies/craig_downsampling_strategy.py	14	9	36%
modyn/selector/internal/selector_strategies/downsampling_strategies/downsampling_scheduler.py	55	2	96%
modyn/selector/internal/selector_strategies/downsampling_strategies/gradmatch_downsampling_strategy.py	12	7	42%
modyn/selector/internal/selector_strategies/downsampling_strategies/gradnorm_downsampling_strategy.py	5	0	100%
modyn/selector/internal/selector_strategies/downsampling_strategies/kcentergreedy_downsampling_strategy.py	12	7	42%
modyn/selector/internal/selector_strategies/downsampling_strategies/loss_downsampling_strategy.py	5	0	100%
modyn/selector/internal/selector_strategies/downsampling_strategies/no_downsampling_strategy.py	14	2	86%
modyn/selector/internal/selector_strategies/downsampling_strategies/submodular_downsampling_strategy.py	19	13	32%
modyn/selector/internal/selector_strategies/downsampling_strategies/uncertainty_downsampling_strategy.py	15	10	33%
modyn/selector/internal/selector_strategies/downsampling_strategies/utils.py	10	0	100%
modyn/selector/internal/selector_strategies/freshness_sampling_strategy.py	114	8	93%
modyn/selector/internal/selector_strategies/new_data_strategy.py	118	8	93%
modyn/selector/internal/selector_strategies/presampling_strategies/abstract_balanced_strategy.py	51	0	100%
modyn/selector/internal/selector_strategies/presampling_strategies/abstract_presampling_strategy.py	24	2	92%
modyn/selector/internal/selector_strategies/presampling_strategies/label_balanced_presampling_strategy.py	5	0	100%
modyn/selector/internal/selector_strategies/presampling_strategies/no_presampling_strategy.py	15	1	93%
modyn/selector/internal/selector_strategies/presampling_strategies/random_no_replacement_presampling_strategy.py	34	0	100%
modyn/selector/internal/selector_strategies/presampling_strategies/random_presampling_strategy.py	15	0	100%
modyn/selector/internal/selector_strategies/presampling_strategies/trigger_balanced_presampling_strategy.py	11	1	91%
modyn/selector/internal/selector_strategies/presampling_strategies/utils.py	13	0	100%
modyn/selector/selector.py	81	14	83%
modyn/selector/selector_entrypoint.py	31	3	90%
modyn/storage/internal/database/models/dataset.py	20	0	100%
modyn/storage/internal/database/models/file.py	17	0	100%
modyn/storage/internal/database/models/sample.py	44	7	84%
modyn/storage/internal/database/storage_base.py	3	0	100%
modyn/storage/internal/database/storage_database_connection.py	53	0	100%
modyn/storage/internal/database/storage_database_utils.py	21	0	100%
modyn/storage/internal/file_watcher/new_file_watcher.py	214	44	79%
modyn/storage/internal/file_watcher/new_file_watcher_watch_dog.py	59	9	85%
modyn/storage/internal/file_wrapper/abstract_file_wrapper.py	23	1	96%
modyn/storage/internal/file_wrapper/binary_file_wrapper.py	49	1	98%
modyn/storage/internal/file_wrapper/csv_file_wrapper.py	94	8	91%
modyn/storage/internal/file_wrapper/file_wrapper_type.py	8	0	100%
modyn/storage/internal/file_wrapper/single_sample_file_wrapper.py	48	2	96%
modyn/storage/internal/filesystem_wrapper/abstract_filesystem_wrapper.py	31	1	97%
modyn/storage/internal/filesystem_wrapper/filesystem_wrapper_type.py	6	0	100%
modyn/storage/internal/filesystem_wrapper/local_filesystem_wrapper.py	52	0	100%
modyn/storage/internal/grpc/grpc_server.py	12	1	92%
modyn/storage/internal/grpc/storage_grpc_servicer.py	156	13	92%
modyn/storage/storage.py	34	1	97%
modyn/storage/storage_entrypoint.py	32	3	91%
modyn/supervisor/entrypoint.py	44	6	86%
modyn/supervisor/internal/evaluation_result_writer/abstract_evaluation_result_writer.py	14	2	86%
modyn/supervisor/internal/evaluation_result_writer/json_result_writer.py	17	0	100%
modyn/supervisor/internal/evaluation_result_writer/tensorboard_result_writer.py	13	0	100%
modyn/supervisor/internal/grpc_handler.py	329	50	85%
modyn/supervisor/internal/triggers/amounttrigger.py	15	0	100%
modyn/supervisor/internal/triggers/timetrigger.py	27	1	96%
modyn/supervisor/internal/triggers/trigger.py	6	0	100%
modyn/supervisor/internal/utils/evaluation_status_tracker.py	23	0	100%
modyn/supervisor/internal/utils/training_status_tracker.py	121	12	90%
modyn/supervisor/supervisor.py	324	41	87%
modyn/tests/common/grpc/test_grpc_helpers.py	3	0	100%
modyn/tests/database/test_abstract_database_connection.py	19	0	100%
modyn/tests/evaluator/internal/dataset/test_evaluation_dataset.py	128	2	98%
modyn/tests/evaluator/internal/grpc/test_evaluator_grpc_server.py	20	0	100%
modyn/tests/evaluator/internal/grpc/test_evaluator_grpc_servicer.py	291	16	95%
modyn/tests/evaluator/internal/metrics/test_accuracy.py	45	0	100%
modyn/tests/evaluator/internal/metrics/test_f1_score.py	58	0	100%
modyn/tests/evaluator/internal/metrics/test_roc_auc.py	31	0	100%
modyn/tests/evaluator/internal/test_metric_factory.py	13	0	100%
modyn/tests/evaluator/internal/test_pytorch_evaluator.py	166	19	89%
modyn/tests/evaluator/test_evaluator.py	30	0	100%
modyn/tests/evaluator/test_evaluator_entrypoint.py	22	0	100%
modyn/tests/metadata_database/models/test_pipelines.py	34	0	100%
modyn/tests/metadata_database/models/test_sample_training_metadata.py	40	0	100%
modyn/tests/metadata_database/models/test_selector_state_metadata.py	46	0	100%
modyn/tests/metadata_database/models/test_trained_models.py	46	0	100%
modyn/tests/metadata_database/models/test_trigger_training_metadata.py	38	0	100%
modyn/tests/metadata_database/models/test_triggers.py	33	0	100%
modyn/tests/metadata_database/test_metadata_database_connection.py	29	0	100%
modyn/tests/metadata_processor/internal/grpc/test_metadata_processor_grpc_servicer.py	26	0	100%
modyn/tests/metadata_processor/internal/grpc/test_metadata_processor_server.py	27	0	100%
modyn/tests/metadata_processor/internal/test_metadata_processor_manager.py	42	3	93%
modyn/tests/metadata_processor/processor_strategies/test_abstract_processor_strategy.py	60	0	100%
modyn/tests/metadata_processor/processor_strategies/test_basic_processor_strategy.py	43	0	100%
modyn/tests/metadata_processor/test_metadata_processor.py	22	3	86%
modyn/tests/metadata_processor/test_metadata_processor_entrypoint.py	22	0	100%
modyn/tests/model_storage/internal/grpc/test_model_storage_grpc_server.py	13	0	100%
modyn/tests/model_storage/internal/grpc/test_model_storage_grpc_servicer.py	83	1	99%
modyn/tests/model_storage/test_model_storage.py	35	5	86%
modyn/tests/model_storage/test_model_storage_entrypoint.py	22	0	100%
modyn/tests/models/test_bert_tokenizer.py	24	0	100%
modyn/tests/models/test_dlrm.py	46	0	100%
modyn/tests/models/test_embedding_recorder.py	27	0	100%
modyn/tests/models/test_fmownet.py	25	0	100%
modyn/tests/models/test_resnet18.py	22	0	100%
modyn/tests/models/test_yearbook_net.py	47	0	100%
modyn/tests/selector/internal/grpc/test_selector_grpc_servicer.py	145	0	100%
modyn/tests/selector/internal/grpc/test_selector_server.py	16	0	100%
modyn/tests/selector/internal/selector_strategies/downsampling_strategies/test_abstract_downsampling_strategy.py	15	0	100%
modyn/tests/selector/internal/selector_strategies/downsampling_strategies/test_gradnorm_downsampling_strategy.py	13	0	100%
modyn/tests/selector/internal/selector_strategies/downsampling_strategies/test_loss_downsampling_strategy.py	17	0	100%
modyn/tests/selector/internal/selector_strategies/downsampling_strategies/test_no_downsampling_strategy.py	5	0	100%
modyn/tests/selector/internal/selector_strategies/downsampling_strategies/test_scheduler.py	114	0	100%
modyn/tests/selector/internal/selector_strategies/presampling_strategies/test_abstract_balanced_strategy.py	14	0	100%
modyn/tests/selector/internal/selector_strategies/presampling_strategies/test_empty_presampling_strategy.py	0	0	100%
modyn/tests/selector/internal/selector_strategies/presampling_strategies/test_label_balanced_presampling_strategy.py	164	0	100%
modyn/tests/selector/internal/selector_strategies/presampling_strategies/test_random_no_replacement_presampling_strategy.py	51	0	100%
modyn/tests/selector/internal/selector_strategies/presampling_strategies/test_random_presampling_strategy.py	94	0	100%
modyn/tests/selector/internal/selector_strategies/presampling_strategies/test_trigger_balanced_presampling.py	139	0	100%
modyn/tests/selector/internal/selector_strategies/test_abstract_selection_strategy.py	220	0	100%
modyn/tests/selector/internal/selector_strategies/test_coreset_strategy.py	232	0	100%
modyn/tests/selector/internal/selector_strategies/test_freshness_sampling_strategy.py	308	0	100%
modyn/tests/selector/internal/selector_strategies/test_new_data_strategy.py	519	0	100%
modyn/tests/selector/internal/test_selector_manager.py	159	3	98%
modyn/tests/selector/internal/trigger_sample/test_trigger_sample_storage.py	157	0	100%
modyn/tests/selector/test_selector.py	89	3	97%
modyn/tests/selector/test_selector_entrypoint.py	26	0	100%
modyn/tests/storage/internal/database/models/test_dataset.py	47	0	100%
modyn/tests/storage/internal/database/models/test_file.py	64	0	100%
modyn/tests/storage/internal/database/models/test_sample.py	73	0	100%
modyn/tests/storage/internal/database/test_database_storage_utils.py	21	2	90%
modyn/tests/storage/internal/database/test_storage_database_connection.py	54	3	94%
modyn/tests/storage/internal/file_watcher/test_new_file_watcher.py	377	13	97%
modyn/tests/storage/internal/file_watcher/test_new_file_watcher_watch_dog.py	95	1	99%
modyn/tests/storage/internal/file_wrapper/test_binary_file_wrapper.py	92	0	100%
modyn/tests/storage/internal/file_wrapper/test_csv_file_wrapper.py	165	1	99%
modyn/tests/storage/internal/file_wrapper/test_file_wrapper_type.py	6	1	83%
modyn/tests/storage/internal/file_wrapper/test_single_sample_file_wrapper.py	90	0	100%
modyn/tests/storage/internal/filesystem_wrapper/test_filesystem_wrapper_type.py	6	1	83%
modyn/tests/storage/internal/filesystem_wrapper/test_local_filesystem_wrapper.py	167	0	100%
modyn/tests/storage/internal/grpc/test_grpc_server.py	6	0	100%
modyn/tests/storage/internal/grpc/test_storage_grpc_servicer.py	273	3	99%
modyn/tests/storage/test_storage.py	42	1	98%
modyn/tests/storage/test_storage_entrypoint.py	21	0	100%
modyn/tests/supervisor/internal/evaluation_result_writer/test_abstract_evaluation_result_writer.py	7	0	100%
modyn/tests/supervisor/internal/evaluation_result_writer/test_json_result_writer.py	16	0	100%
modyn/tests/supervisor/internal/evaluation_result_writer/test_tensorboard_result_writer.py	21	0	100%
modyn/tests/supervisor/internal/test_grpc_handler.py	326	0	100%
modyn/tests/supervisor/internal/triggers/test_amounttrigger.py	30	0	100%
modyn/tests/supervisor/internal/triggers/test_timetrigger.py	26	0	100%
modyn/tests/supervisor/internal/triggers/test_trigger.py	5	0	100%
modyn/tests/supervisor/internal/utils/test_evaluation_status_tracker.py	41	0	100%
modyn/tests/supervisor/internal/utils/test_training_status_tracker.py	133	0	100%
modyn/tests/supervisor/test_entrypoint.py	39	0	100%
modyn/tests/supervisor/test_supervisor.py	414	2	99%
modyn/tests/trainer_server/internal/data/key_sources/test_local_key_source.py	89	0	100%
modyn/tests/trainer_server/internal/data/key_sources/test_selector_key_source.py	92	0	100%
modyn/tests/trainer_server/internal/data/test_data_utils.py	22	1	95%
modyn/tests/trainer_server/internal/data/test_local_dataset_writer.py	59	0	100%
modyn/tests/trainer_server/internal/data/test_online_dataset.py	335	3	99%
modyn/tests/trainer_server/internal/data/test_per_class_online_dataset.py	53	3	94%
modyn/tests/trainer_server/internal/grpc/test_trainer_server_grpc_server.py	17	0	100%
modyn/tests/trainer_server/internal/grpc/test_trainer_server_grpc_servicer.py	389	8	98%
modyn/tests/trainer_server/internal/metadata_collector/test_metadata_collector.py	41	0	100%
modyn/tests/trainer_server/internal/trainer/metadata_pytorch_callbacks/test_loss_callback.py	51	1	98%
modyn/tests/trainer_server/internal/trainer/remote_downsamplers/deepcore_comparison_tests_utils.py	21	1	95%
modyn/tests/trainer_server/internal/trainer/remote_downsamplers/test_abstract_matrix_downsampling_strategy.py	75	0	100%
modyn/tests/trainer_server/internal/trainer/remote_downsamplers/test_abstract_remote_downsampling_strategy.py	12	0	100%
modyn/tests/trainer_server/internal/trainer/remote_downsamplers/test_craig_remote_downsampling.py	249	0	100%
modyn/tests/trainer_server/internal/trainer/remote_downsamplers/test_get_tensor_subset.py	56	0	100%
modyn/tests/trainer_server/internal/trainer/remote_downsamplers/test_remote_gradmatch_downsampling_strategy.py	116	0	100%
modyn/tests/trainer_server/internal/trainer/remote_downsamplers/test_remote_gradnorm_downsample.py	92	0	100%
modyn/tests/trainer_server/internal/trainer/remote_downsamplers/test_remote_kcenter_downsampling_strategy.py	104	0	100%
modyn/tests/trainer_server/internal/trainer/remote_downsamplers/test_remote_loss_downsample.py	82	0	100%
modyn/tests/trainer_server/internal/trainer/remote_downsamplers/test_remote_submodular_downsampling_strategy.py	101	0	100%
modyn/tests/trainer_server/internal/trainer/remote_downsamplers/test_remote_uncertainty_downsampling_strategy.py	49	0	100%
modyn/tests/trainer_server/internal/trainer/test_pytorch_trainer.py	361	33	91%
modyn/tests/trainer_server/test_trainer_server.py	34	0	100%
modyn/tests/trainer_server/test_trainer_server_entrypoint.py	22	0	100%
modyn/tests/utils/test_utils.py	123	0	100%
modyn/trainer_server/custom_lr_schedulers/dlrm_lr_scheduler/dlrm_scheduler.py	33	33	0%
modyn/trainer_server/internal/dataset/data_utils.py	17	2	88%
modyn/trainer_server/internal/dataset/key_sources/abstract_key_source.py	21	5	76%
modyn/trainer_server/internal/dataset/key_sources/local_key_source.py	23	1	96%
modyn/trainer_server/internal/dataset/key_sources/selector_key_source.py	54	2	96%
modyn/trainer_server/internal/dataset/local_dataset_writer.py	65	4	94%
modyn/trainer_server/internal/dataset/online_dataset.py	253	23	91%
modyn/trainer_server/internal/dataset/per_class_online_dataset.py	14	0	100%
modyn/trainer_server/internal/grpc/trainer_server_grpc_server.py	22	0	100%
modyn/trainer_server/internal/grpc/trainer_server_grpc_servicer.py	235	37	84%
modyn/trainer_server/internal/metadata_collector/metadata_collector.py	33	0	100%
modyn/trainer_server/internal/mocks/mock_metadata_processor.py	22	2	91%
modyn/trainer_server/internal/trainer/metadata_pytorch_callbacks/base_callback.py	15	3	80%
modyn/trainer_server/internal/trainer/metadata_pytorch_callbacks/loss_callback.py	21	0	100%
modyn/trainer_server/internal/trainer/pytorch_trainer.py	458	149	67%
modyn/trainer_server/internal/trainer/remote_downsamplers/abstract_matrix_downsampling_strategy.py	66	4	94%
modyn/trainer_server/internal/trainer/remote_downsamplers/abstract_per_label_remote_downsample_strategy.py	9	1	89%
modyn/trainer_server/internal/trainer/remote_downsamplers/abstract_remote_downsampling_strategy.py	32	3	91%
modyn/trainer_server/internal/trainer/remote_downsamplers/deepcore_utils/cossim.py	28	17	39%
modyn/trainer_server/internal/trainer/remote_downsamplers/deepcore_utils/euclidean.py	29	12	59%
modyn/trainer_server/internal/trainer/remote_downsamplers/deepcore_utils/k_center_greedy.py	38	4	89%
modyn/trainer_server/internal/trainer/remote_downsamplers/deepcore_utils/orthogonal_matching_pursuit.py	66	34	48%
modyn/trainer_server/internal/trainer/remote_downsamplers/deepcore_utils/shuffling.py	9	0	100%
modyn/trainer_server/internal/trainer/remote_downsamplers/deepcore_utils/submodular_function.py	103	15	85%
modyn/trainer_server/internal/trainer/remote_downsamplers/deepcore_utils/submodular_optimizer.py	116	78	33%
modyn/trainer_server/internal/trainer/remote_downsamplers/remote_craig_downsampling.py	95	7	93%
modyn/trainer_server/internal/trainer/remote_downsamplers/remote_grad_match_downsampling_strategy.py	17	1	94%
modyn/trainer_server/internal/trainer/remote_downsamplers/remote_gradnorm_downsampling.py	37	3	92%
modyn/trainer_server/internal/trainer/remote_downsamplers/remote_kcenter_greedy_downsampling_strategy.py	15	0	100%
modyn/trainer_server/internal/trainer/remote_downsamplers/remote_loss_downsampling.py	29	3	90%
modyn/trainer_server/internal/trainer/remote_downsamplers/remote_submodular_downsampling_strategy.py	30	3	90%
modyn/trainer_server/internal/trainer/remote_downsamplers/remote_uncertainty_downsampling_strategy.py	61	18	70%
modyn/trainer_server/internal/utils/metric_type.py	3	0	100%
modyn/trainer_server/internal/utils/trainer_messages.py	4	0	100%
modyn/trainer_server/internal/utils/training_info.py	51	2	96%
modyn/trainer_server/internal/utils/training_process_info.py	10	0	100%
modyn/trainer_server/trainer_server.py	19	0	100%
modyn/trainer_server/trainer_server_entrypoint.py	32	3	91%
modyn/utils/utils.py	131	12	91%
TOTAL	16920	1352	92%
Coverage	HTML	written	to
================	1930	passed,	771