PPO vs SAC — which do you pick?
mediumAnswer
- PPO: on-policy, simple to implement + tune, works everywhere reasonably, standard for RLHF of LLMs. SAC: off-policy, sample-efficient (uses replay), maximum entropy → robust, best for continuous control (robotics).
- Rule: (1) discrete + easy tuning + big rollouts → PPO.
- (2) Continuous + sample efficiency matters → SAC.
- (3) Large-scale distributed → PPO with IMPALA-style actors.
- (4) LLM alignment → PPO (RLHF standard).
Check yourself — multiple choice
- Same thing
- PPO: on-policy, simple, RLHF standard, discrete/scale friendly; SAC: off-policy, sample-efficient, max-entropy, continuous control (robotics)
- Random
- Only PPO
PPO: on-policy simple RLHF; SAC: off-policy sample-efficient continuous.
#policy-methods#actor-critic
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