hongzimao / pensieve

Neural Adaptive Video Streaming with Pensieve (SIGCOMM '17)
http://web.mit.edu/pensieve/
MIT License
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'last quality' vs 'last bitrate' #112

Open harshita1804 opened 4 years ago

harshita1804 commented 4 years ago

What is the difference between the two?... is'nt the last quality proportional to the last bitrate?

hongzimao commented 4 years ago

They should mean the same thing - i.e., the bitrate from the previous action. We were just using different names at different points during the project development. Sorry for the confusion.

harshita1804 commented 4 years ago

My question was for MPC server, I see there to compute smoothness_diffs, both these values are used which would be equal right?

hongzimao commented 4 years ago

They should be equal. You can also try logging the values of these variables just to make sure.

harshita1804 commented 4 years ago

I also had an implementation question, I was trying to implement robust mpc, but my mpc always chooses the highest or the lowest bitrate, any ideas on how to solve this issue, I have been stuck with it for the last 2 days. Any suggestion will be highly appreciated

hongzimao commented 4 years ago

We also provided a robust MPC implementation in https://github.com/hongzimao/pensieve/blob/master/rl_server/robust_mpc_server.py#L200 Perhaps you can check the output from your implementation and compare with ours?

harshita1804 commented 4 years ago

I did actually, so the problem is my algo keeps choosing the highest bitrate, I feel there is something wrong with my reward function

hongzimao commented 4 years ago

It's likely - I think you have a few viable ideas to try out. Why don't you log the reward from our implementation and compare with yours? robustMPC should be deterministic and all results should be reproducible. Debugging this down might be tedious but doing it right can be interesting.

harshita1804 commented 4 years ago

yeah, it worked actually, I was using the linear reward, but disregarded the fact that my bitrates were in bits/sec which were huge so the reward was very high converting to mbps helped.. thankyou for your time!