Why the JupyterNoteBook cell is still running after the progress bars have been finished?

[thatmee]

Here is the picture of the cell. I noticed that all progress bars finished in about 3mins. However, the cell is still running and stops after 8mins. Why would this happen? Thank you!

[tmvfb]

Second this. In my case, the dataset has 100+ million rows, and the delay is much longer than 8 mins.
As it seems a relatively new issue, it may be connected with using Jupyter Notebook 7 or Pandas 2.0+.

UPD: Allocating more RAM to WSL, hiding the progress bar, setting use_memory_fs=True and running script in a new notebook actually helped to significantly speed up the process, so the problem may be related to RAM, and not the library.

Some details:
Operating System: Ubuntu 22.04.2 LTS (WSL 2)
Python version: 3.10.12
Pandas version: 2.1.1
Pandarallel version: 1.6.5
Jupyter Notebook version: 7.0.2

That's what I get if I stop the cell execution when all threads are at 100%:

Process ForkPoolWorker-14:
Process ForkPoolWorker-15:
Process ForkPoolWorker-16:
Process ForkPoolWorker-17:
Traceback (most recent call last):
  File "/usr/lib/python3.10/multiprocessing/queues.py", line 365, in get
    res = self._reader.recv_bytes()
Traceback (most recent call last):
  File "/usr/lib/python3.10/multiprocessing/connection.py", line 216, in recv_bytes
    buf = self._recv_bytes(maxlength)
  File "/usr/lib/python3.10/multiprocessing/pool.py", line 114, in worker
    task = get()
  File "/usr/lib/python3.10/multiprocessing/queues.py", line 364, in get
    with self._rlock:
  File "/usr/lib/python3.10/multiprocessing/connection.py", line 414, in _recv_bytes
    buf = self._recv(4)
  File "/usr/lib/python3.10/multiprocessing/connection.py", line 379, in _recv
    chunk = read(handle, remaining)
  File "/usr/lib/python3.10/multiprocessing/synchronize.py", line 95, in __enter__
    return self._semlock.__enter__()
KeyboardInterrupt
KeyboardInterrupt

During handling of the above exception, another exception occurred:


During handling of the above exception, another exception occurred:

Traceback (most recent call last):
Traceback (most recent call last):
Traceback (most recent call last):
Traceback (most recent call last):
  File "/usr/lib/python3.10/multiprocessing/process.py", line 314, in _bootstrap
    self.run()
  File "/usr/lib/python3.10/multiprocessing/pool.py", line 114, in worker
    task = get()
  File "/usr/lib/python3.10/multiprocessing/process.py", line 314, in _bootstrap
    self.run()
  File "/usr/lib/python3.10/multiprocessing/process.py", line 108, in run
    self._target(*self._args, **self._kwargs)
  File "/usr/lib/python3.10/multiprocessing/pool.py", line 114, in worker
    task = get()
  File "/usr/lib/python3.10/multiprocessing/queues.py", line 364, in get
    with self._rlock:
  File "/usr/lib/python3.10/multiprocessing/process.py", line 108, in run
    self._target(*self._args, **self._kwargs)
  File "/usr/lib/python3.10/multiprocessing/pool.py", line 114, in worker
    task = get()
  File "/usr/lib/python3.10/multiprocessing/queues.py", line 364, in get
    with self._rlock:
  File "/usr/lib/python3.10/multiprocessing/synchronize.py", line 95, in __enter__
    return self._semlock.__enter__()
  File "/usr/lib/python3.10/multiprocessing/pool.py", line 114, in worker
    task = get()
  File "/usr/lib/python3.10/multiprocessing/synchronize.py", line 95, in __enter__
    return self._semlock.__enter__()
  File "/usr/lib/python3.10/multiprocessing/queues.py", line 365, in get
    res = self._reader.recv_bytes()
KeyboardInterrupt
KeyboardInterrupt
KeyboardInterrupt

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
KeyboardInterrupt

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3.10/multiprocessing/process.py", line 314, in _bootstrap
    self.run()
  File "/usr/lib/python3.10/multiprocessing/process.py", line 314, in _bootstrap
    self.run()
  File "/usr/lib/python3.10/multiprocessing/process.py", line 108, in run
    self._target(*self._args, **self._kwargs)
  File "/usr/lib/python3.10/multiprocessing/pool.py", line 114, in worker
    task = get()
KeyboardInterrupt
  File "/usr/lib/python3.10/multiprocessing/process.py", line 108, in run
    self._target(*self._args, **self._kwargs)
  File "/usr/lib/python3.10/multiprocessing/pool.py", line 114, in worker
    task = get()
KeyboardInterrupt
---------------------------------------------------------------------------
KeyboardInterrupt                         Traceback (most recent call last)
    [... skipping hidden 1 frame]

Cell In[22], line 1
----> 1 convert_timestamp(train)

File ~/sleep/lib/parallel.py:31, in convert_timestamp(df)
     30 gc.collect()
---> 31 df["timestamp"] = df.timestamp.parallel_apply(to_correct_format)

File ~/.local/lib/python3.10/site-packages/pandarallel/core.py:444, in parallelize_with_pipe.<locals>.closure(data, user_defined_function, *user_defined_function_args, **user_defined_function_kwargs)
    442         progress_bars.set_error(worker_index)
--> 444 results = results_promise.get()
    446 return data_type.reduce(results, reduce_extra)

File /usr/lib/python3.10/multiprocessing/pool.py:768, in ApplyResult.get(self, timeout)
    767 def get(self, timeout=None):
--> 768     self.wait(timeout)
    769     if not self.ready():

File /usr/lib/python3.10/multiprocessing/pool.py:765, in ApplyResult.wait(self, timeout)
    764 def wait(self, timeout=None):
--> 765     self._event.wait(timeout)

File /usr/lib/python3.10/threading.py:607, in Event.wait(self, timeout)
    606 if not signaled:
--> 607     signaled = self._cond.wait(timeout)
    608 return signaled

File /usr/lib/python3.10/threading.py:320, in Condition.wait(self, timeout)
    319 if timeout is None:
--> 320     waiter.acquire()
    321     gotit = True

KeyboardInterrupt: 

During handling of the above exception, another exception occurred:

KeyboardInterrupt                         Traceback (most recent call last)
KeyboardInterrupt: 

[nalepae]

Pandaral·lel is looking for a maintainer!
If you are interested, please open an GitHub issue.

[shermansiu]

@thatmee You mentioned that the problem is likely related to the amount of RAM available and not a problem with pandarallel itself. Do you have any other problems?

I'm tempted to close this issue otherwise (or if there isn't a reply in a while).