Storing values larger than 2 GB

[mitar]

Is your feature request related to a problem? Please describe.

I would want to store values larger than 2 GB.

Describe the solution you'd like

Be able to configure SegmentSize to a value larger than 2 GB and then be able to store larger files. Currently this is not possible because there is a hard-coded limit in value size to MaxInt32 value. (In fact, I think there is a bug and it should really be MaxUint32 on 64bit systems.)

I suggest the limit is raised to MaxInt64 on 64bit systems.

Describe alternatives you've considered

I could split large value into multiple smaller values on my side and then store all of those splits manually and recombine them.

Additional context

It seems to me that this is just to support mmap on 32 bit systems and there is really no design limitation why not to support larger values? On my system, I have:

$ grep -m1 "address sizes" /proc/cpuinfo 
address sizes	: 39 bits physical, 48 bits virtual

So a bit less than 2^47 (128 TiB) could be the max limit for mmap on my system.