recsplit don't store MPH when keys are monotonically increasing integers.

[sudeepdino008]

get rid of MPHT for cases when keys are incrementing integers. These can be stored simply as ef.
Discussion

[wmitsuda]

FYI: read the discussion on Discord about baseId + ef, I also had this requirement in my non-merged branch, maybe we can dedup some code in the future when it is merged: https://github.com/erigontech/erigon/blob/wmitsuda/ef-optimization-experiments/erigon-lib/recsplit/eliasfano32/rebased_elias_fano.go

[sudeepdino008]

FYI: read the discussion on Discord about baseId + ef, I also had this requirement in my non-merged branch, maybe we can dedup some code in the future when it is merged: https://github.com/erigontech/erigon/blob/wmitsuda/ef-optimization-experiments/erigon-lib/recsplit/eliasfano32/rebased_elias_fano.go

So it seems like we will already have the no-MPH thingy with your optimizations @wmitsuda?