Retrieve request so slow

[novichikhin]

Why is the retrieve request so slow? @moloney

import asyncio
import time

from dcm._globals import QueryLevel
from dcm.net import DcmNode, LocalEntity
from dcm.node import RemoteNode
from pydicom import Dataset


async def main() -> None:
    local = LocalEntity(DcmNode("localhost", "MY_AE_TITLE", 1111))
    mypacs = RemoteNode("localhost", "CONQUESTSRV1", 5678)

    query = Dataset()
    query.StudyID = "433724515"

    datasets = []

    qr = await local.query(
        mypacs,
        query=query,
        level=QueryLevel.IMAGE
    )

    start_perf_count = time.perf_counter()

    async for ds in local.retrieve(remote=mypacs, query_res=qr):
        datasets.append(ds)

    print(f"Datasets length: {len(datasets)}, perf counter time: {time.perf_counter() - start_perf_count}")


if __name__ == "__main__":
    asyncio.run(main())

Output: Datasets length: 384, perf counter time: 9.486925958000938

import time
from typing import List

from pydicom.dataset import Dataset

from pynetdicom import AE, evt, sop_class, StoragePresentationContexts
from pydicom.uid import ImplicitVRLittleEndian


class DicomClient:

    def __init__(self, hostname, port, ae_title):
        self.port = port
        self.hostname = hostname
        self.ae_title = ae_title

    def fetch(self, datasets: List[Dataset]):
        def handle_store(event):
            dataset = event.dataset
            dataset.file_meta = event.file_meta

            datasets.append(dataset)

            return 0x0000

        handlers = [(evt.EVT_C_STORE, handle_store)]

        ae = AE(ae_title=self.ae_title)

        ae.add_requested_context(
            sop_class._QR_CLASSES["PatientRootQueryRetrieveInformationModelMove"],
            ImplicitVRLittleEndian
        )
        ae.supported_contexts = StoragePresentationContexts

        scp = ae.start_server(("127.0.0.1", 1111), block=False, evt_handlers=handlers)

        ds = Dataset()
        ds.QueryRetrieveLevel = "IMAGE"
        ds.StudyID = "433724515"

        assoc = ae.associate(
            addr=self.hostname,
            port=self.port,
            ae_title=self.ae_title,
            evt_handlers=handlers
        )

        if assoc.is_established:
            responses = assoc.send_c_move(
                ds,
                "MY_AE_TITLE",
                sop_class._QR_CLASSES["PatientRootQueryRetrieveInformationModelMove"]
            )

            """
            for (status, _) in responses:
                if status:
                    pass
                else:
                    print('Connection timed out, was aborted or received invalid response')
            """

            assoc.release()
        else:
            print('Association rejected, aborted or never connected')

        scp.shutdown()


def main():
    client = DicomClient(
        hostname="localhost",
        port=5678,
        ae_title="CONQUESTSRV1"
    )

    datasets = []

    start_perf_count = time.perf_counter()

    client.fetch(datasets=datasets)

    print(f"Datasets length: {len(datasets)}, perf counter time: {time.perf_counter() - start_perf_count}")


if __name__ == "__main__":
    main()

Output: Datasets length: 384, perf counter time: 2.612817499997618

[novichikhin]

I also wanted to ask why, when using FastAPI application (with gunicorn + uvicorn worker), requests are very much slowed down.

Application runs in one process and one thread.