Update prover scaling formula

core/server/src/prover_server/scaler.rs

@@ -3,6 +3,7 @@
 // Built-in deps
 use std::time::{Duration, Instant};
 // Workspace deps
+use models::config_options::parse_env;
 use storage::ConnectionPool;
 
 /// Disable the prover service after 5 minutes with no blocks to generate.
@@ -52,25 +53,10 @@ impl ScalerOracle {
         // simplest possible solution is preferred.
 
         let storage = self.db.access_storage()?;
-        let jobs = storage.prover_schema().unstarted_jobs_count()?;
+        let pending_jobs = storage.prover_schema().pending_jobs_count()?;
+        let idle_provers: u64 = parse_env("IDLE_PROVERS");
+        let provers_required = pending_jobs + idle_provers;
 
-        if jobs != 0 {
-            self.last_time_with_blocks = Instant::now();
-        }
-
-        if working_provers_count == 0 && jobs == 0 {
-            // No provers active, no jobs as well => no need to start one.
-            return Ok(0);
-        }
-
-        let provers_required = if self.last_time_with_blocks.elapsed() >= PROVER_DISABLE_THRESHOLD {
-            // Long time no blocks => shutdown prover.
-            0
-        } else {
-            // Either a new block has appeared or not so long without blocks => start/retain prover.
-            1
-        };
-
-        Ok(provers_required)
+        Ok(provers_required as u32)
     }
 }

core/storage/src/prover/mod.rs

@@ -56,6 +56,15 @@ impl<'a> ProverSchema<'a> {
         })
     }
 
+    pub fn pending_jobs_count(&self) -> QueryResult<u64> {
+        self.0.conn().transaction(|| {
+            let last_committed_block = BlockSchema(&self.0).get_last_committed_block()? as u64;
+            let last_verified_block = BlockSchema(&self.0).get_last_verified_block()? as u64;
+
+            Ok(last_committed_block - last_verified_block)
+        })
+    }
+
     /// Given the block size, chooses the next block to prove for the certain prover.
     /// Returns `None` if either there are no blocks of given size to prove, or
     /// there is already an ongoing job for non-proved block.

etc/env/dev.env.example

@@ -108,6 +108,8 @@ PROVER_SERVER_URL=http://0.0.0.0:8088
 PROVER_SERVER_BIND=0.0.0.0:8088
 # Prover container kubernetes resources.(adjust according to BLOCK_CHUNK_SIZES selected)
 PROVER_MIN_RESOURCES="{\"requests\": {\"cpu\": 1, \"memory\": \"6Gi\"}}"
+# Number of idle provers running (to scale up faster)
+IDLE_PROVERS=1
 
 SERVER_API_HOST=localhost
 SERVER_API_HOST_CERT=""