Async pipelined FPWR + 4kHz: exec 245us->24us, RTT 2ms->1.25-1.5ms
- FPWR fire-and-forget: two alternating leaked tx slots, or()-driven 20us kick to reach sendable, poll_once reap after next spin-detect (late=0 over 350k cycles). Fixes: reap placement, poll_once kick - exec drops to 24us mean, freeing budget for 4kHz (250us) operation - 4kHz verified: TwinCAT PLC at 4001.8Hz, lag 5-6 cycles (RTT 1.25-1.5ms); J1900 effective 2.9kHz - FPRD poll cost (71us x N) exceeds 250us budget, occasional frame miss - Conclusion: J1900 write wait never contributed to lag; the 4-stage pipeline is TwinCAT IO mapping + bridge forwarding
This commit is contained in:
Tony Cao
parent
3a26aea082
commit
8c1f519526
61
scripts/tc-deploy-retry-4khz.ps1
Normal file
61
scripts/tc-deploy-retry-4khz.ps1
Normal file
|
|
@ -0,0 +1,61 @@
|
|||
#Requires -RunAsAdministrator
|
||||
#Requires -Version 5.1
|
||||
$ErrorActionPreference = 'Continue'
|
||||
|
||||
function Invoke-Com {
|
||||
param([scriptblock]$Fn, [int]$Retries = 30, [int]$DelayMs = 2000)
|
||||
for ($i = 0; $i -lt $Retries; $i++) {
|
||||
try { return & $Fn } catch {
|
||||
$hr = $_.Exception.HResult
|
||||
if ($hr -eq -2147418111) { Start-Sleep -Milliseconds $DelayMs; continue }
|
||||
throw
|
||||
}
|
||||
}
|
||||
throw "COM call rejected $Retries times (RPC_E_CALL_REJECTED)"
|
||||
}
|
||||
|
||||
Write-Host "=== Deploy 8B with RPC retry ==="
|
||||
$dte = Invoke-Com { New-Object -ComObject TcXaeShell.DTE.17.0 }
|
||||
Invoke-Com { $dte.MainWindow.Visible = $true } | Out-Null
|
||||
try { Invoke-Com { $dte.SuppressUI = $false } | Out-Null } catch {}
|
||||
Invoke-Com { $dte.Solution.Open('C:\Users\tonycao\work\twincat3-auto-cli\TwinCAT_EL6695_Primary_4kHz\TwinCATProject1.sln') } | Out-Null
|
||||
Write-Host "solution opened"
|
||||
|
||||
$sm = $null
|
||||
for ($i = 0; $i -lt 40; $i++) {
|
||||
try { $sm = Invoke-Com { $dte.Solution.Projects.Item(1).Object } -Retries 3 -DelayMs 3000; if ($sm) { break } } catch { Write-Host " waiting sysmgr..." }
|
||||
}
|
||||
if (-not $sm) { Write-Host "FATAL: no sysmgr"; exit 1 }
|
||||
Write-Host "sysmgr OK"
|
||||
Invoke-Com { $sm.SetTargetNetId('169.254.176.217.1.1') } | Out-Null
|
||||
|
||||
Write-Host "building..."
|
||||
try { Invoke-Com { $dte.ExecuteCommand('Build.BuildSolution') } -Retries 10 | Out-Null } catch { Write-Host "build cmd: $_" }
|
||||
# wait for build done (BuildState 3 = done)
|
||||
$done = $false
|
||||
for ($i = 0; $i -lt 90; $i++) {
|
||||
try {
|
||||
$bs = Invoke-Com { $dte.Solution.SolutionBuild.BuildState } -Retries 5 -DelayMs 3000
|
||||
$bi = Invoke-Com { $dte.Solution.SolutionBuild.LastBuildInfo } -Retries 5 -DelayMs 1000
|
||||
if ($bs -eq 3) { Write-Host "build done (LastBuildInfo=$bi) after $($i*2)s"; $done = $true; break }
|
||||
} catch { Write-Host " build poll err: $_" }
|
||||
Start-Sleep -Seconds 2
|
||||
}
|
||||
if (-not $done) { Write-Host "WARN: build state never reached done" }
|
||||
|
||||
# dump build errors if any
|
||||
try {
|
||||
$ew = $dte.ToolWindows.ErrorList
|
||||
Write-Host "error list check skipped"
|
||||
} catch {}
|
||||
|
||||
Write-Host "activating..."
|
||||
Invoke-Com { $sm.ActivateConfiguration() } -Retries 30 -DelayMs 3000 | Out-Null
|
||||
Write-Host "activated"
|
||||
Start-Sleep 10
|
||||
Write-Host "restarting runtime..."
|
||||
Invoke-Com { $sm.StartRestartTwinCAT() } -Retries 30 -DelayMs 3000 | Out-Null
|
||||
Write-Host "restart issued"
|
||||
Start-Sleep 12
|
||||
try { Write-Host "IsTwinCATStarted=$($sm.IsTwinCATStarted)" } catch {}
|
||||
Write-Host "=== done ==="
|
||||
83
src/main.rs
83
src/main.rs
|
|
@ -755,6 +755,17 @@ async fn run(cfg: &Config) -> Result<(), Box<dyn std::error::Error>> {
|
|||
let mut prev_rx8 = [0u8; 8]; // spin-lock: previous payload (change detect)
|
||||
let mut last_fresh: Option<Instant> = None; // spin-lock: last fresh-data instant
|
||||
|
||||
// Async pipelined FPWR: two alternating leaked tx slots so the in-flight
|
||||
// write future can hold a 'static buffer while the response is reaped
|
||||
// at the start of the next cycle.
|
||||
let tx_slot_a = Box::leak(Box::new([0u8; 8]));
|
||||
let tx_slot_b = Box::leak(Box::new([0u8; 8]));
|
||||
let mut tx_slot_toggle = false;
|
||||
let mut pending_tx: Option<
|
||||
std::pin::Pin<Box<dyn std::future::Future<Output = Result<(), ethercrab::error::Error>> + '_>>,
|
||||
> = None;
|
||||
let mut tx_late: u64 = 0;
|
||||
|
||||
let mut aborted: Option<String> = None;
|
||||
|
||||
loop {
|
||||
|
|
@ -823,6 +834,21 @@ async fn run(cfg: &Config) -> Result<(), Box<dyn std::error::Error>> {
|
|||
let t0 = Instant::now();
|
||||
cyc += 1;
|
||||
|
||||
// Reap async FPWR kicked last cycle: the spin-detect above gave the
|
||||
// response ~one full cycle to arrive, so this should never block.
|
||||
if let Some(mut f) = pending_tx.take() {
|
||||
match futures_lite::future::poll_once(f.as_mut()).await {
|
||||
Some(Ok(_)) => {}
|
||||
Some(Err(_)) => {
|
||||
tx_err += 1;
|
||||
}
|
||||
None => {
|
||||
tx_late += 1;
|
||||
let _ = f.await;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if !spin_mode {
|
||||
// 1. Read SM3 (TwinCAT data via bridge)
|
||||
let t_rx0 = Instant::now();
|
||||
|
|
@ -913,14 +939,47 @@ async fn run(cfg: &Config) -> Result<(), Box<dyn std::error::Error>> {
|
|||
tx_buf[264..268].copy_from_slice(&(jitter_ns as i32).to_le_bytes());
|
||||
}
|
||||
|
||||
let t_tx0 = Instant::now();
|
||||
let tx_ok = ethercrab::Command::fpwr(station, SM_TX_ADDR)
|
||||
.send(&maindevice, &tx_buf[..PAYLOAD_LEN])
|
||||
.await
|
||||
.is_ok();
|
||||
tx_rtt_st.push(t_tx0.elapsed().as_nanos() as i64);
|
||||
if !tx_ok {
|
||||
tx_err += 1;
|
||||
if spin_mode && PAYLOAD_LEN == 8 {
|
||||
// Async pipelined FPWR: kick the frame onto the wire now
|
||||
// (poll_once drives it to sendable), reap response next
|
||||
// cycle. Frees ~240us of blocking write time per cycle.
|
||||
let p = if tx_slot_toggle {
|
||||
tx_slot_b.as_mut_ptr()
|
||||
} else {
|
||||
tx_slot_a.as_mut_ptr()
|
||||
};
|
||||
tx_slot_toggle = !tx_slot_toggle;
|
||||
let slot: &'static mut [u8] =
|
||||
unsafe { std::slice::from_raw_parts_mut(p, PAYLOAD_LEN) };
|
||||
slot.copy_from_slice(&tx_buf[..PAYLOAD_LEN]);
|
||||
let mut fut = Box::pin(
|
||||
ethercrab::Command::fpwr(station, SM_TX_ADDR).send(&maindevice, &slot[..]),
|
||||
);
|
||||
// Kick: drive the write future for up to ~20us so the frame
|
||||
// is marked sendable and the TX thread puts it on the wire
|
||||
// NOW. poll_once alone does not reach sendable state.
|
||||
let t_kick = Instant::now();
|
||||
let _ = futures_lite::future::or(
|
||||
async { fut.as_mut().await.is_ok() },
|
||||
async {
|
||||
while t_kick.elapsed().as_micros() < 20 {
|
||||
futures_lite::future::yield_now().await;
|
||||
}
|
||||
false
|
||||
},
|
||||
)
|
||||
.await;
|
||||
pending_tx = Some(fut);
|
||||
} else {
|
||||
let t_tx0 = Instant::now();
|
||||
let tx_ok = ethercrab::Command::fpwr(station, SM_TX_ADDR)
|
||||
.send(&maindevice, &tx_buf[..PAYLOAD_LEN])
|
||||
.await
|
||||
.is_ok();
|
||||
tx_rtt_st.push(t_tx0.elapsed().as_nanos() as i64);
|
||||
if !tx_ok {
|
||||
tx_err += 1;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
|
|
@ -1051,13 +1110,14 @@ async fn run(cfg: &Config) -> Result<(), Box<dyn std::error::Error>> {
|
|||
let proc_val = tc_seq.wrapping_mul(7).wrapping_add(3);
|
||||
let stale_pct = if cyc > 0 { (rx_stale * 100 / cyc) } else { 0 };
|
||||
println!(
|
||||
"S tms={} cyc={} raw={} proc={} txe={} rxe={} stale={}% mono={} cerr={} mism={} e0={} e1={}",
|
||||
"S tms={} cyc={} raw={} proc={} txe={} rxe={} late={} stale={}% mono={} cerr={} mism={} e0={} e1={}",
|
||||
start.elapsed().as_millis(),
|
||||
cyc,
|
||||
tc_seq,
|
||||
proc_val,
|
||||
tx_err,
|
||||
rx_err,
|
||||
tx_late,
|
||||
stale_pct,
|
||||
rx_nonmono,
|
||||
comp_err,
|
||||
|
|
@ -1073,6 +1133,11 @@ async fn run(cfg: &Config) -> Result<(), Box<dyn std::error::Error>> {
|
|||
}
|
||||
}
|
||||
|
||||
// Reap any in-flight async FPWR before reporting
|
||||
if let Some(f) = pending_tx.take() {
|
||||
let _ = f.await;
|
||||
}
|
||||
|
||||
// ---- Final report ----
|
||||
println!("\n=== timing stats ===");
|
||||
jitter_st.report(1000, "us");
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user