[vicaya]

For reads, sure. LSMs are optimized for writes, while LMDB, which is a nice B-tree implementation is optimized for reads.

LSMs are getting popular because it's harder to scale durable writes than reads, which can be handled (in many cases independently) by caching.

[hyc_symas]

LSMs are solving a problem that is rapidly becoming irrelevant due to the multiple NVRAM technologies entering the market. With NVDIMMs, MRAM, FeRAM, PRAM, etc., all your writes can be durable for free. And if you'll notice in that HyperDex benchmark I posted, the LSM write performance was still worse than LMDB, while wasting several times more CPU.

Going forward, power efficiency will still be crucial - for as long as civilization persists. But optimizing durable writes will be about as useful as optimizing delay loops.