Are consensus parameters governance modifiable?

[rootulp]

The SDK now manages consensus parameters via the x/params module and are changed via governance proposals.

Source: #6197 (comment)

However, I'm having a difficult time figuring out how to modify consensus parameters via the governance module. Is it actually possible to modify a consensus parameter (e.g. evidence.MaxAgeNumBlocks) via governance? If yes, can you please share a link to an example of how to do this or a test that verifies this behavior?

My question is specific to Cosmos SDK 0.46.x but I'm also curious if this has changed in subsequent releases. Additional context in celestiaorg/celestia-app#2418 (comment).

[julienrbrt]

For v0.47+ the params are stored in the x/consensus module instead of x/params and can be changed by a MsgUpdateParams msg included in a gov v1 proposal:
https://github.com/cosmos/cosmos-sdk/blob/v0.50.0-rc.0/proto/cosmos/consensus/v1/tx.proto#L23-L42

For v0.46, as it still using x/params, you need to submit a gov v1beta1 parameter change proposal.

[rootulp]

For v0.46, I'm attempting to create a gov parameter change proposal.

• What subspace do consensus params occupy?
• Where can I find a list of keys for consensus params? For example, what key does the evidence param MaxAgeNumBlocks use?

[rootulp]

Update: based on this code, I think subspace is baseapp and the key I'm looking for is EvidenceParams.

[rootulp]

you need to submit a gov v1beta1 parameter change proposal

Can you please link to the type you're referring to? I couldn't find it in https://github.com/cosmos/cosmos-sdk/tree/release/v0.46.x/x/gov/types/v1beta1

[rootulp]

The only place I can see consensus params getting set is here and I still don't see how a governance proposal can invoke that.

[tac0turtle]

This is where the values would be updated:

cosmos-sdk/x/params/proposal_handler.go

Line 26 in f1dfe60

func handleParameterChangeProposal(ctx sdk.Context, k keeper.Keeper, p *proposal.ParameterChangeProposal) error {

, the link you provided is only called in initchain to provide the params to comet at the start.