Cli: better estimate of epoch time elapsed/remaining (#15893)

* Add rpc_client api for getRecentPerformanceSamples

* Prep fn for variable avg slot time

* Use recent-perf-samples to more-accurately estimate epoch completed times

* Spell out average

cli-output/src/cli_output.rs

@@ -19,7 +19,7 @@ use {
         RpcVoteAccountInfo,
     },
     solana_sdk::{
-        clock::{self, Epoch, Slot, UnixTimestamp},
+        clock::{Epoch, Slot, UnixTimestamp},
         epoch_info::EpochInfo,
         hash::Hash,
         native_token::lamports_to_sol,
@@ -231,12 +231,8 @@ pub struct CliSlotStatus {
 pub struct CliEpochInfo {
     #[serde(flatten)]
     pub epoch_info: EpochInfo,
-}
-
-impl From<EpochInfo> for CliEpochInfo {
-    fn from(epoch_info: EpochInfo) -> Self {
-        Self { epoch_info }
-    }
+    #[serde(skip)]
+    pub average_slot_time_ms: u64,
 }
 
 impl QuietDisplay for CliEpochInfo {}
@@ -286,16 +282,16 @@ impl fmt::Display for CliEpochInfo {
             "Epoch Completed Time:",
             &format!(
                 "{}/{} ({} remaining)",
-                slot_to_human_time(self.epoch_info.slot_index),
-                slot_to_human_time(self.epoch_info.slots_in_epoch),
-                slot_to_human_time(remaining_slots_in_epoch)
+                slot_to_human_time(self.epoch_info.slot_index, self.average_slot_time_ms),
+                slot_to_human_time(self.epoch_info.slots_in_epoch, self.average_slot_time_ms),
+                slot_to_human_time(remaining_slots_in_epoch, self.average_slot_time_ms)
             ),
         )
     }
 }
 
-fn slot_to_human_time(slot: Slot) -> String {
-    humantime::format_duration(Duration::from_millis(slot * clock::DEFAULT_MS_PER_SLOT)).to_string()
+fn slot_to_human_time(slot: Slot, slot_time_ms: u64) -> String {
+    humantime::format_duration(Duration::from_secs((slot * slot_time_ms) / 1000)).to_string()
 }
 
 #[derive(Serialize, Deserialize, Default)]

cli/src/cluster_query.rs

@@ -993,7 +993,20 @@ pub fn process_get_epoch(rpc_client: &RpcClient, _config: &CliConfig) -> Process
 }
 
 pub fn process_get_epoch_info(rpc_client: &RpcClient, config: &CliConfig) -> ProcessResult {
-    let epoch_info: CliEpochInfo = rpc_client.get_epoch_info()?.into();
+    let epoch_info = rpc_client.get_epoch_info()?;
+    let average_slot_time_ms = rpc_client
+        .get_recent_performance_samples(Some(60))
+        .map(|samples| {
+            let (slots, secs) = samples.iter().fold((0, 0), |(slots, secs), sample| {
+                (slots + sample.num_slots, secs + sample.sample_period_secs)
+            });
+            (secs as u64 * 1000) / slots
+        })
+        .unwrap_or(clock::DEFAULT_MS_PER_SLOT);
+    let epoch_info = CliEpochInfo {
+        epoch_info,
+        average_slot_time_ms,
+    };
     Ok(config.output_format.formatted_string(&epoch_info))
 }
 
@@ -1008,8 +1021,8 @@ pub fn process_get_slot(rpc_client: &RpcClient, _config: &CliConfig) -> ProcessR
 }
 
 pub fn process_get_block_height(rpc_client: &RpcClient, _config: &CliConfig) -> ProcessResult {
-    let epoch_info: CliEpochInfo = rpc_client.get_epoch_info()?.into();
-    Ok(epoch_info.epoch_info.block_height.to_string())
+    let epoch_info = rpc_client.get_epoch_info()?;
+    Ok(epoch_info.block_height.to_string())
 }
 
 pub fn parse_show_block_production(matches: &ArgMatches<'_>) -> Result<CliCommandInfo, CliError> {

client/src/rpc_client.rs

@@ -644,6 +644,13 @@ impl RpcClient {
         self.send(RpcRequest::GetEpochSchedule, Value::Null)
     }
 
+    pub fn get_recent_performance_samples(
+        &self,
+        limit: Option<usize>,
+    ) -> ClientResult<Vec<RpcPerfSample>> {
+        self.send(RpcRequest::GetRecentPerformanceSamples, json!([limit]))
+    }
+
     pub fn get_identity(&self) -> ClientResult<Pubkey> {
         let rpc_identity: RpcIdentity = self.send(RpcRequest::GetIdentity, Value::Null)?;
 

client/src/rpc_request.rs

@@ -34,6 +34,7 @@ pub enum RpcRequest {
     GetMultipleAccounts,
     GetProgramAccounts,
     GetRecentBlockhash,
+    GetRecentPerformanceSamples,
     GetSnapshotSlot,
     GetSignatureStatuses,
     GetSlot,
@@ -90,6 +91,7 @@ impl fmt::Display for RpcRequest {
             RpcRequest::GetMultipleAccounts => "getMultipleAccounts",
             RpcRequest::GetProgramAccounts => "getProgramAccounts",
             RpcRequest::GetRecentBlockhash => "getRecentBlockhash",
+            RpcRequest::GetRecentPerformanceSamples => "getRecentPerformanceSamples",
             RpcRequest::GetSnapshotSlot => "getSnapshotSlot",
             RpcRequest::GetSignatureStatuses => "getSignatureStatuses",
             RpcRequest::GetSlot => "getSlot",