feat: increase max RPC connections to 1000

CHANGELOG.md

@@ -53,6 +53,8 @@
 
 - [#6471](https://github.com/ChainSafe/forest/pull/6471): Moved `forest-tool state` subcommand to `forest-dev`.
 
+- [#6527](https://github.com/ChainSafe/forest/issues/6527): Increased the maximum number of allowed connections to the RPC server to 1000. This can be further configured via the `FOREST_RPC_MAX_CONNECTIONS` environment variable.
+
 ### Removed
 
 ### Fixed

docs/docs/users/reference/env_variables.md

@@ -20,6 +20,7 @@ process.
 | `FOREST_FORCE_TRUST_PARAMS`                               | 1 or true                        | false                                          | 1                                                             | Trust the parameters downloaded from the Cloudflare/IPFS                                                              |
 | `IPFS_GATEWAY`                                            | URL                              | `https://proofs.filecoin.io/ipfs/`             | `https://proofs.filecoin.io/ipfs/`                            | The IPFS gateway to use for downloading proofs parameters                                                             |
 | `FOREST_RPC_DEFAULT_TIMEOUT`                              | Duration (in seconds)            | 60                                             | 10                                                            | The default timeout for RPC calls                                                                                     |
+| `FOREST_RPC_MAX_CONNECTIONS`                              | positive integer                 | 1000                                           | 42                                                            | Maximum number of allowed connections for the RPC server                                                              |
 | `FOREST_MAX_CONCURRENT_REQUEST_RESPONSE_STREAMS_PER_PEER` | positive integer                 | 10                                             | 10                                                            | the maximum concurrent streams per peer for request-response-based p2p protocols                                      |
 | `FOREST_BLOCK_DELAY_SECS`                                 | positive integer                 | Depends on the network                         | 30                                                            | Duration of each tipset epoch                                                                                         |
 | `FOREST_PROPAGATION_DELAY_SECS`                           | positive integer                 | Depends on the network                         | 20                                                            | How long to wait for a block to propagate through the network                                                         |

src/rpc/mod.rs

@@ -466,6 +466,15 @@ static DEFAULT_REQUEST_TIMEOUT: LazyLock<Duration> = LazyLock::new(|| {
         .unwrap_or(Duration::from_secs(60))
 });
 
+/// Default maximum connections for the RPC server. This needs to be high enough to
+/// accommodate the regular usage for RPC providers.
+static DEFAULT_MAX_CONNECTIONS: LazyLock<u32> = LazyLock::new(|| {
+    env::var("FOREST_RPC_MAX_CONNECTIONS")
+        .ok()
+        .and_then(|it| it.parse().ok())
+        .unwrap_or(1000)
+});
+
 const MAX_REQUEST_BODY_SIZE: u32 = 64 * 1024 * 1024;
 const MAX_RESPONSE_BODY_SIZE: u32 = MAX_REQUEST_BODY_SIZE;
 
@@ -565,6 +574,7 @@ where
                     // Default size (10 MiB) is not enough for methods like `Filecoin.StateMinerActiveSectors`
                     .max_request_body_size(MAX_REQUEST_BODY_SIZE)
                     .max_response_body_size(MAX_RESPONSE_BODY_SIZE)
+                    .max_connections(*DEFAULT_MAX_CONNECTIONS)
                     .set_id_provider(RandomHexStringIdProvider::new())
                     .build(),
             )