[tahoe-dev] How large can a Small Distributed Mutable File be?

[Brian Warner]

> I'm reading that document now, and it suggests that you should use  
> the SDMF feature only for files < 1 MB in size.  This raises the  
> question in my mind -- what's the practical limit?

Note that another limit is memory: the SDMF assumption-of-smallness allows me
to hold the entire file in RAM, as well as all the generated shares. This
gives us a RAM footprint of approximately 4x the filesize.

Part of the "MDMF" task ("Medium" instead of "Small") is to do the extra work
to encode files one segment at a time, to bring the memory footprint back
down to match our CHK file encoding/decoding code. But since the first
customer of mutable files will be dirnodes, we decided that SDMF was a
reasonable first step.

back to the code,
 -Brian