The root chunk is huge

[aboodman]

Currently the root map encodes the type of every dataset. Clients must download this chunk even though nobody ever really uses it.

I think that the thing to do here is to just change Noms to have this root map have the type Map<string, Ref<Value>>.

[aboodman]

See also #2848

[aboodman]

@arv can you estimate difficulty for this?

[aboodman]

It makes attic UI load slowly, but it's somewhat of a temporary problem that will be addressed by other work we have planned.

[aboodman]

Also, would it be a serialization change?

[aboodman]

Update: I realize this might be easier because the type of this map should be Map<string, Ref<Value>>, not Map<string, Value> (the commits are out-of-line).

[aboodman]

@rafael-atticlabs, @arv, @cmasone-attic seems like would be best options for this, but I think @rafael-atticlabs has least on his plate. Can you take it?

[aboodman]

Here is an example of a huge root chunk (16MB) from the laudman db. I'm going to delete some things from this so I wanted to preserve the horribleness for investigation.

!? noms show --raw laudman::#k3s4kee1b0pnortbf94oi0hipsbei7pb | wc -c
 16863431

This chunk is a Map<string, Ref<T|U|V|...> of size 36. So almost all of this 16MB is type info. The type header alone is 8MB:

!? noms show --raw laudman::#k3s4kee1b0pnortbf94oi0hipsbei7pb@type | wc -c
 8429657