Auction starts based on current oracle price; not locked price

[rowgraus]

No description provided.

[Chris-Hibbert]

I think the title is describing a (predicted) bug rather than the desired state. The current version of the PR (#7000) uses the most recent locked price as the basis for starting the auction. I think this is what we want.

[Chris-Hibbert]

I'm in a state of confusion. What would help me is if one of you added something to the issue (these comments seem to be email only, and aren't visible there) saying what the desired state is. As I said in my initial comment, I think the title is describing a bug rather than a goal. Rowland's message of Feb. 22 seems to be saying that the goal matches the current code. (liquidation is based on locked price; auction start is based on current oracle price) Brendan's message seems to be asking for a change. (auction start based on most conservative (is that highest or lowest?) of locked and current prices.) Please add something to the Issue and say what approach is desired.

…

On Tue, Mar 28, 2023 at 8:29 PM otoole-brendan ***@***.***> wrote: @Chris-Hibbert <https://github.com/Chris-Hibbert> just confirming the latest here is auction would start using most conservative price whether that's the locked price or the current oracle price right? (seems to be confirmed by Rowland from the RMIT trip) — Reply to this email directly, view it on GitHub <#6948 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ADGAZXBNNU57YS4KHFQN27LW6OT7ZANCNFSM6AAAAAAUVZ4DN4> . You are receiving this because you were mentioned.Message ID: ***@***.***>

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[otoole-brendan]

@Chris-Hibbert I deleted my comment as I had incorrectly conflated the price we use for creating/adjusting vaults (which is the most conservative) - in this case you are right, we use current oracle price for auction start not locked price. Apologies for the confusion!

[Chris-Hibbert]

We agreed that the current behavior is correct.

The auction uses the locked price for deciding which vaults to liquidate. When the auction starts, the prices are based on the most recent oracle price, scaled up or down according to the parameters. Every round of the auction is scaled from the single oracle price captured at the starting time of the auction.