blockworks-foundation
/
mango-v4
mirror of https://github.com/blockworks-foundation/mango-v4.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Settle pnl: Move fee-computation to PerpMarket 

So it can be used in client code to decide what accounts to settle.
This commit is contained in:
Christian Kamm 2023-02-15 11:24:09 +01:00
parent 722c5ff10b
commit a3a6d9d636
2 changed files with 44 additions and 41 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
programs/mango-v4/src/instructions/perp_settle_pnl.rs
View File

@ -135,7 +135,7 @@ pub fn perp_settle_pnl(ctx: Context<PerpSettlePnl>) -> Result<()> {
b_settle_health,
);
let fee = compute_settle_fee(&perp_market, a_liq_end_health, a_maint_health, settlement)?;
let fee = perp_market.compute_settle_fee(settlement, a_liq_end_health, a_maint_health)?;
a_perp_position.record_settle(settlement);
b_perp_position.record_settle(-settlement);
@ -236,43 +236,3 @@ pub fn perp_settle_pnl(ctx: Context<PerpSettlePnl>) -> Result<()> {
msg!("settled pnl = {}, fee = {}", settlement, fee);
Ok(())
}
pub fn compute_settle_fee(
perp_market: &PerpMarket,
source_liq_end_health: I80F48,
source_maint_health: I80F48,
settlement: I80F48,
) -> Result<I80F48> {
assert!(source_maint_health >= source_liq_end_health);
// A percentage fee is paid to the settler when the source account's health is low.
// That's because the settlement could avoid it getting liquidated: settling will
// increase its health by actualizing positive perp pnl.
let low_health_fee = if source_liq_end_health < 0 {
let fee_fraction = I80F48::from_num(perp_market.settle_fee_fraction_low_health);
if source_maint_health < 0 {
cm!(settlement * fee_fraction)
} else {
cm!(settlement
* fee_fraction
* (-source_liq_end_health / (source_maint_health - source_liq_end_health)))
}
} else {
I80F48::ZERO
};
// The settler receives a flat fee
let flat_fee = I80F48::from_num(perp_market.settle_fee_flat);
// Fees only apply when the settlement is large enough
let fee = if settlement >= perp_market.settle_fee_amount_threshold {
cm!(low_health_fee + flat_fee).min(settlement)
} else {
I80F48::ZERO
};
// Safety check to prevent any accidental negative transfer
require!(fee >= 0, MangoError::SettlementAmountMustBePositive);
Ok(fee)
}

43
programs/mango-v4/src/state/perp_market.rs
View File

@ -6,6 +6,7 @@ use fixed::types::I80F48;
use static_assertions::const_assert_eq;
use crate::accounts_zerocopy::KeyedAccountReader;
use crate::error::MangoError;
use crate::logs::PerpUpdateFundingLog;
use crate::state::orderbook::Side;
use crate::state::{oracle, TokenIndex};
@ -366,6 +367,48 @@ impl PerpMarket {
Ok(socialized_loss)
}
/// Returns the fee for settling `settlement` when the negative-pnl side has the given
/// health values.
pub fn compute_settle_fee(
&self,
settlement: I80F48,
source_liq_end_health: I80F48,
source_maint_health: I80F48,
) -> Result<I80F48> {
assert!(source_maint_health >= source_liq_end_health);
// A percentage fee is paid to the settler when the source account's health is low.
// That's because the settlement could avoid it getting liquidated: settling will
// increase its health by actualizing positive perp pnl.
let low_health_fee = if source_liq_end_health < 0 {
let fee_fraction = I80F48::from_num(self.settle_fee_fraction_low_health);
if source_maint_health < 0 {
cm!(settlement * fee_fraction)
} else {
cm!(settlement
* fee_fraction
* (-source_liq_end_health / (source_maint_health - source_liq_end_health)))
}
} else {
I80F48::ZERO
};
// The settler receives a flat fee
let flat_fee = I80F48::from_num(self.settle_fee_flat);
// Fees only apply when the settlement is large enough
let fee = if settlement >= self.settle_fee_amount_threshold {
cm!(low_health_fee + flat_fee).min(settlement)
} else {
I80F48::ZERO
};
// Safety check to prevent any accidental negative transfer
require!(fee >= 0, MangoError::SettlementAmountMustBePositive);
Ok(fee)
}
/// Creates default market for tests
pub fn default_for_tests() -> PerpMarket {
PerpMarket {