How often to reseed the NIST CTR_DRBG with AES256_CTR Even at a high consumption rate of 100,000 generations per second, it would take decades to exhaust the NIST recommended reseed interval of 2**48 invocations of DRBG _generate(). Should one even care to reseed?
(REF: NIST SP 800-90A, Rev 1.0)
As usual, the answer is: it depends.

It mainly depends on two factors:


Do you have a source of entropy and how good is it?
What's your environment and your threat model?


The benefit of re-seeding your DRBG should be clear: If the state of your DRBG gets compromised at any point, an attacker can re-compute all the outputs of the DRBG following up until the last reseed which limits the damage in case of an successful attack.

Now for the question you may have: Can a re-seed hurt security? No, it can't because information from the last DRBG state is included, transferring initial entropy into the new state and adding new entropy.

So for the first point: Assume you have a good RNG, then re-seeding as often as possible is a good idea that highly limits the risk associated with a state-compromise. If you however have a bad RNG or none at all, you could still try to re-seed, but then it's also a question of the effort involved in doing the re-seed and whether this effort is worth the minimal gain.

Now for the second point: The threat model. This really is your answer to the question: "what access to my device(s) does the attacker have?". If you have secure hardware for the DRBG and an attacker can at most get software-level access or only have a remote view, chances are that a state-compromise won't happen. If the attacker however can get hands-on with the device and try all their best in extracting the state (as you'd be able to with a stolen smart card for example), then advanced attacks like DPA need consideration. If you're sure that such advanced attacks aren't realistic (because breaking the RNG wouldn't outweigh the cost of developing and deploying these attacks), then you can go without a re-seed. If an attacker has a motivation to try really hard to get into the device they'll probably try all those attacks and depending on how good the secured hardware is, chances are they'll succeed.