program: amm-spread-inventory-spread-adj-base-spread-lb (#1803)

Author: 0xbigz

programs/drift/src/controller/position/tests.rs

@@ -940,10 +940,10 @@ fn amm_ref_price_offset_decay_logic() {
     assert_eq!(
         sspreads,
         [
-            7147, 6937, 6727, 6517, 6307, 6097, 6077, 6057, 6037, 6017, 5807, 5596, 5386, 5176,
-            4966, 4756, 4546, 4336, 4126, 3916, 3706, 3496, 3286, 3076, 2866, 2656, 2446, 2236,
-            2026, 1816, 1626, 1455, 1302, 1164, 1040, 928, 827, 736, 654, 581, 515, 456, 402, 354,
-            311, 272, 237, 205, 177, 151, 128, 107, 87, 67, 47, 27, 7, 6, 6, 6
+            7150, 6940, 6730, 6520, 6310, 6100, 6080, 6060, 6040, 6020, 5810, 5600, 5390, 5180,
+            4970, 4760, 4550, 4340, 4130, 3920, 3710, 3500, 3290, 3080, 2870, 2660, 2450, 2240,
+            2030, 1820, 1630, 1459, 1306, 1168, 1044, 932, 831, 740, 658, 585, 519, 460, 406, 358,
+            315, 276, 241, 209, 181, 155, 132, 111, 91, 71, 51, 31, 11, 10, 10, 10
         ]
     );
 }
@@ -1108,10 +1108,11 @@ fn amm_negative_ref_price_offset_decay_logic() {
     assert_eq!(
         sspreads,
         [
-            207, 207, 207, 207, 207, 207, 17, 17, 17, 17, 207, 206, 206, 206, 206, 206, 206, 206,
-            206, 206, 206, 206, 206, 206, 206, 206, 206, 206, 206, 206, 206, 206, 206, 206, 206,
-            206, 206, 206, 126, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
-            6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6
+            210, 210, 210, 210, 210, 210, 20, 20, 20, 20, 210, 210, 210, 210, 210, 210, 210, 210,
+            210, 210, 210, 210, 210, 210, 210, 210, 210, 210, 210, 210, 210, 210, 210, 210, 210,
+            210, 210, 210, 130, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+            10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+            10, 10
         ]
     );
     assert_eq!(

programs/drift/src/math/amm_spread.rs

@@ -458,24 +458,24 @@ pub fn calculate_spread(
         let adjustment: u64 = amm_inventory_spread_adjustment
             .cast::<i64>()?
             .unsigned_abs();
-        long_spread = long_vol_spread.max(
+        long_spread = max(half_base_spread_u64, long_vol_spread).max(
             long_spread
                 .saturating_sub(long_spread.saturating_mul(adjustment).safe_div(100)?)
                 .max(1),
         );
-        short_spread = short_vol_spread.max(
+        short_spread = max(half_base_spread_u64, short_vol_spread).max(
             short_spread
                 .saturating_sub(short_spread.saturating_mul(adjustment).safe_div(100)?)
                 .max(1),
         );
     } else if amm_inventory_spread_adjustment > 0 {
         let adjustment = amm_inventory_spread_adjustment.cast()?;
-        long_spread = long_vol_spread.max(
+        long_spread = max(half_base_spread_u64, long_vol_spread).max(
             long_spread
                 .saturating_add(long_spread.saturating_mul(adjustment).safe_div_ceil(100)?)
                 .max(1),
         );
-        short_spread = short_vol_spread.max(
+        short_spread = max(half_base_spread_u64, short_vol_spread).max(
             short_spread
                 .saturating_add(short_spread.saturating_mul(adjustment).safe_div_ceil(100)?)
                 .max(1),