refactor optimal retention to minimize workload per memorization & fix progress goes backwards (#3065)

* Feat/optimal retention for minimal workload per memorization

* ./ninja fix:minilints

* update to FSRS-rs 0.5.2

* update to FSRS-rs 0.5.3

* ./ninja fix:minilints

* 'estimated retention' -> 'predicted optimal retention'; add warning (dae)

Cargo.lock

@@ -1792,9 +1792,9 @@ dependencies = [
 
 [[package]]
 name = "fsrs"
-version = "0.5.0"
+version = "0.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7c7e6a1986cc2b7a64445d84e2c453ecd8d95dcf90b797205c54573697e10b17"
+checksum = "50f8d2ba5394c6e36fa01d88df181206bcae8b7a4ef3c5653eb4d635e3f595e4"
 dependencies = [
  "burn",
  "itertools 0.12.1",

Cargo.toml

@@ -35,7 +35,7 @@ git = "https://github.com/ankitects/linkcheck.git"
 rev = "184b2ca50ed39ca43da13f0b830a463861adb9ca"
 
 [workspace.dependencies.fsrs]
-version = "0.5.0"
+version = "0.5.3"
 # git = "https://github.com/open-spaced-repetition/fsrs-rs.git"
 # rev = "58ca25ed2bc4bb1dc376208bbcaed7f5a501b941"
 # path = "../open-spaced-repetition/fsrs-rs"

cargo/licenses.json

@@ -1198,7 +1198,7 @@
   },
   {
     "name": "fsrs",
-    "version": "0.5.0",
+    "version": "0.5.3",
     "authors": "Open Spaced Repetition",
     "repository": "https://github.com/open-spaced-repetition/fsrs-rs",
     "license": "BSD-3-Clause",

ftl/core/deck-config.ftl

@@ -357,7 +357,7 @@ deck-config-get-params = Get Params
 deck-config-fsrs-on-all-clients =
     Please ensure all of your Anki clients are Anki(Mobile) 23.10+ or AnkiDroid 2.17+. FSRS will
     not work correctly if one of your clients is older.
-deck-config-estimated-retention = Estimated retention: { $num }
+deck-config-predicted-optimal-retention = Predicted optimal retention: { $num }
 deck-config-complete = { $num }% complete.
 deck-config-iterations = Iteration: { $count }...
 deck-config-reschedule-cards-on-change = Reschedule cards on change

proto/anki/scheduler.proto

@@ -373,12 +373,10 @@ message FsrsReview {
 
 message ComputeOptimalRetentionRequest {
   repeated float weights = 1;
-  uint32 deck_size = 2;
+  uint32 days_to_simulate = 2;
-  uint32 days_to_simulate = 3;
+  uint32 max_interval = 3;
-  uint32 max_minutes_of_study_per_day = 4;
+  string search = 4;
-  uint32 max_interval = 5;
+  double loss_aversion = 5;
-  string search = 6;
-  double loss_aversion = 7;
 }
 
 message ComputeOptimalRetentionResponse {

rslib/src/scheduler/fsrs/retention.rs

@@ -28,12 +28,15 @@ impl Collection {
             invalid_input!("no days to simulate")
         }
         let p = self.get_optimal_retention_parameters(&req.search)?;
+        let learn_span = req.days_to_simulate as usize;
+        let learn_limit = 10;
+        let deck_size = learn_span * learn_limit;
         Ok(fsrs
             .optimal_retention(
                 &SimulatorConfig {
-                    deck_size: req.deck_size as usize,
+                    deck_size,
                     learn_span: req.days_to_simulate as usize,
-                    max_cost_perday: req.max_minutes_of_study_per_day as f64 * 60.0,
+                    max_cost_perday: f64::MAX,
                     max_ivl: req.max_interval as f64,
                     recall_costs: [p.recall_secs_hard, p.recall_secs_good, p.recall_secs_easy],
                     forget_cost: p.forget_secs,
@@ -50,7 +53,7 @@ impl Collection {
                         p.review_rating_probability_easy,
                     ],
                     loss_aversion: req.loss_aversion,
-                    learn_limit: usize::MAX,
+                    learn_limit,
                     review_limit: usize::MAX,
                 },
                 &req.weights,

ts/deck-options/FsrsOptions.svelte

@@ -55,9 +55,7 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
         | undefined;
 
     const optimalRetentionRequest = new ComputeOptimalRetentionRequest({
-        deckSize: 10000,
         daysToSimulate: 365,
-        maxMinutesOfStudyPerDay: 30,
         lossAversion: 2.5,
     });
     $: if (optimalRetentionRequest.daysToSimulate > 3650) {
@@ -249,7 +247,7 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
         if (!retention) {
             return "";
         }
-        return tr.deckConfigEstimatedRetention({ num: retention.toFixed(2) });
+        return tr.deckConfigPredictedOptimalRetention({ num: retention.toFixed(2) });
     }
 </script>
 
@@ -348,15 +346,6 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
     <details>
         <summary>{tr.deckConfigComputeOptimalRetention()} (experimental)</summary>
 
-        <SpinBoxRow
-            bind:value={optimalRetentionRequest.deckSize}
-            defaultValue={10000}
-            min={100}
-            max={99999}
-        >
-            <SettingTitle>Deck size</SettingTitle>
-        </SpinBoxRow>
-
         <SpinBoxRow
             bind:value={optimalRetentionRequest.daysToSimulate}
             defaultValue={365}
@@ -366,15 +355,6 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
             <SettingTitle>Days to simulate</SettingTitle>
         </SpinBoxRow>
 
-        <SpinBoxRow
-            bind:value={optimalRetentionRequest.maxMinutesOfStudyPerDay}
-            defaultValue={30}
-            min={1}
-            max={1800}
-        >
-            <SettingTitle>Minutes study/day</SettingTitle>
-        </SpinBoxRow>
-
         <button
             class="btn {computingRetention ? 'btn-warning' : 'btn-primary'}"
             disabled={!computingRetention && computing}
@@ -389,6 +369,12 @@ License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 
         {#if optimalRetention}
             {estimatedRetention(optimalRetention)}
+            {#if optimalRetention > $config.desiredRetention}
+                <Warning
+                    warning="Your desired retention is below optimal. Increasing it is recommended."
+                    className="alert-warning"
+                />
+            {/if}
         {/if}
         <div>{computeRetentionProgressString}</div>
     </details>