Cache recent blocks in memory to reduce load on the db

graph/src/env/store.rs

@@ -66,6 +66,9 @@ pub struct EnvVarsStore {
     /// Set by the environment variable `GRAPH_REMOVE_UNUSED_INTERVAL`
     /// (expressed in minutes). The default value is 360 minutes.
     pub remove_unused_interval: chrono::Duration,
+    /// Set by the environment variable
+    /// `GRAPH_STORE_RECENT_BLOCKS_CACHE_CAPACITY`. The default value is 10 blocks.
+    pub recent_blocks_cache_capacity: usize,
 
     // These should really be set through the configuration file, especially for
     // `GRAPH_STORE_CONNECTION_MIN_IDLE` and
@@ -123,6 +126,7 @@ impl From<InnerStore> for EnvVarsStore {
             remove_unused_interval: chrono::Duration::minutes(
                 x.remove_unused_interval_in_minutes as i64,
             ),
+            recent_blocks_cache_capacity: x.recent_blocks_cache_capacity,
             connection_timeout: Duration::from_millis(x.connection_timeout_in_millis),
             connection_min_idle: x.connection_min_idle,
             connection_idle_timeout: Duration::from_secs(x.connection_idle_timeout_in_secs),
@@ -158,6 +162,8 @@ pub struct InnerStore {
     connection_try_always: EnvVarBoolean,
     #[envconfig(from = "GRAPH_REMOVE_UNUSED_INTERVAL", default = "360")]
     remove_unused_interval_in_minutes: u64,
+    #[envconfig(from = "GRAPH_STORE_RECENT_BLOCKS_CACHE_CAPACITY", default = "10")]
+    recent_blocks_cache_capacity: usize,
 
     // These should really be set through the configuration file, especially for
     // `GRAPH_STORE_CONNECTION_MIN_IDLE` and

rust-toolchain.toml

@@ -1,3 +1,3 @@
 [toolchain]
-channel = "1.65.0"
+channel = "1.66.0"
 profile = "default"

store/postgres/src/block_store.rs

@@ -8,7 +8,7 @@ use std::{
 use graph::{
     blockchain::ChainIdentifier,
     components::store::BlockStore as BlockStoreTrait,
-    prelude::{error, warn, BlockNumber, BlockPtr, Logger},
+    prelude::{error, warn, BlockNumber, BlockPtr, Logger, ENV_VARS},
 };
 use graph::{
     constraint_violation,
@@ -372,6 +372,7 @@ impl BlockStore {
             status,
             sender,
             pool,
+            ENV_VARS.store.recent_blocks_cache_capacity,
         );
         if create {
             store.create(&ident)?;