Loop setparams: swap fee PPM must be non-zero

[sotarules]

trafficstars

Expected behavior

Friends, I have some channels being managed by autoloop but after doing some initial balancing, many are now disqualified.

{
    "loop_out": [
    ],
    "loop_in": [
    ],
    "disqualified": [
        {
            "channel_id": "772583939960995840",
            "pubkey": null,
            "reason": "AUTO_REASON_PREPAY"
        },
        {
            "channel_id": "727345633609580545",
            "pubkey": null,
            "reason": "AUTO_REASON_LIQUIDITY_OK"
        },
        {
            "channel_id": "727090546821365761",
            "pubkey": null,
            "reason": "AUTO_REASON_LIQUIDITY_OK"
        },
        {
            "channel_id": "733005919405408257",
            "pubkey": null,
            "reason": "AUTO_REASON_PREPAY"
        },
        {
            "channel_id": "772686194551422977",
            "pubkey": null,
            "reason": "AUTO_REASON_PREPAY"
        },
        {
            "channel_id": "733522689825767425",
            "pubkey": null,
            "reason": "AUTO_REASON_LIQUIDITY_OK"
        }
    ]
}

As you can see the disqualification reason is AUTO_REASON_PREPAY. As part of my ongoing experimentation, I want to relax this constraint to allow the system to go forward with the loop out irrespective of AUTO_REASON_PREPAY so I'm trying to set the limits.

loop setparams --maxprepay 20000 command should set prepayment maximum for no-show.

Actual behavior

[loop] rpc error: code = Unknown desc = swap fee PPM must be non-zero

I've tried to set a bunch of different parameters, but many of them cause the system to issue this same message. I've searched everywhere but I cannot find a good guide on all of the constraints on the parameters and how to set them. If there is some sequence I need to do that would be good information to have. Also, an example of a several example configurations for people that have different tolerances regarding costs, including how to set all of the parameters.

Examples:

• Tightwad configuration
• Conservative configuration
• Liberal Configuration
• Test Configuration (guaranteed to swap almost always)

To reproduce

I can reproduce 100% of the time on 0.18.0-beta.

System information

Using stand-alone loop through command line interface. Loop version is 0.18.0-beta I am building from go using go install ./.. This is on a Qotom i5 Celeron machine running Ubuntu Impish.