why does insert_and_evict not support in hybrid mode(HBM+HMEM)?

[haiqiang-zhang]

I understand that the current semantics of "evict" refer to evicting data from HBM. However, I believe supporting eviction from hybrid HKV (HBM + HMEM) would also be quite useful. It seems that the functionality is already implemented, but currently restricted with an exception:
throw std::runtime_error("Only allow insert_and_evict in pure HBM mode.");

Could you please clarify why insert_and_evict is not supported in hybrid mode?

[jiashuy]

Thanks @haiqiang-zhang for your question.
Hi @rhdong , do you think it make sense to remove this runtime check in insert_and_evict API? My concern is that it will be slow on performance. But for @haiqiang-zhang , the feature is more important.

[rhdong]

Thanks @haiqiang-zhang for your question. Hi @rhdong , do you think it make sense to remove this runtime check in insert_and_evict API? My concern is that it will be slow on performance. But for @haiqiang-zhang , the feature is more important.

Hi @jiashuy @haiqiang-zhang, I'm OK with this, but we’ll need additional tests to verify everything.
cc @Lifann — could you take a look at the question when you get a chance? Thanks!