Drop used voteCounter vats

[Chris-Hibbert]

What is the Problem Being Solved?

Each time the EC takes a vote on MainNet, a new voteCounter vat is created. the outcome of the vote isn't recorded anywhere, so the vats aren't deleted upon completion. Currently, 46 out of 123 vats on mainNet are voteCounters which have finished. They shouldn't ever be paged in, so they won't use up computrons, but it's space that has to be preserved.

Description of the Design

We want to make vote outcomes visible both on-chain and off-line.

VStorage will suffice for the off-line store. Committee have access to the outcome, and could start recording it, and could also make it accessible. Committees are not upgradeable, so we'd have to wait until we're willing to replace them.

Before terminating the existing vats, we would need to also write code to backfill the past questions and make their data available both on- and off-line.

Security Considerations

N/A

Scaling Considerations

yes.

Test Plan

verify that clients of the outcomes won't be harmed by cleaning up these vats.

Upgrade Considerations

yes.

[Chris-Hibbert]

Later discussions clarified that

• vstorage doesn't need to continue to store all the history. It's okay for some data to be retrievable from vstorage
• "publisher updates that can be received off-chain should be receivable on-chain too." There's no need to make all info that was once available via notification perpetually available.

I think we can terminate old voteCounters whenever it's convenient.
@warner