From f676fb96de1615d3098b8cfcde09e9a82d90843d Mon Sep 17 00:00:00 2001
From: l0ng-ai <24760907+l0ng-ai@users.noreply.github.com>
Date: Tue, 11 Aug 2026 09:36:51 +0800
Subject: [PATCH] perf(wsl): stop asking twice whether a distro is ready
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Every pane on a WSL workspace ran `ensure_wsl_server` from the client
before it even connected to the daemon — and then the daemon ran the very
same probe inside `router::open_link` before opening the link. Two full
rounds of five serial `wsl.exe` calls, to learn one fact.

The client's copy bought nothing. It threw the answer away and kept only
the error, which the route ack reports just as well; and the consent
question for a first install still finds its way here, because the daemon
runs its probe under `RouteSetup::blocking`, which installs the relay that
turns that question into a frame on this connection.

Measured on a distro that was already running and connected: 800ms to open
a tab, down to 440ms. Issue #454 is the same code on a machine where one
`wsl.exe` round trip takes 3.3s, where the duplicate was costing 15s a tab.
---
 src/terminal/remote.rs | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/terminal/remote.rs b/src/terminal/remote.rs
index 51ba3362..4d01b14b 100644
--- a/src/terminal/remote.rs
+++ b/src/terminal/remote.rs
@@ -2105,11 +2105,18 @@ fn connect_routed(route: &PaneRoute) -> anyhow::Result<Stream> {
 
     tty7_core::host::guard_off_ui();
 
-    if let crate::daemon::router::RouteTarget::Wsl { distro } = &header.target {
-        crate::daemon::install::wsl::ensure_wsl_server(distro)
-            .map_err(|e| anyhow::anyhow!("prepare tty7-server in WSL `{distro}`: {e}"))?;
-    }
-
+    // No `ensure_wsl_server` here on purpose. The daemon runs exactly the same
+    // probe inside `router::open_link` before it opens the link, so asking from
+    // this side too bought nothing and cost a second full round of `wsl.exe`
+    // invocations — five of them, serially, on every single pane. On a machine
+    // where a `wsl.exe` round trip is slow (issue #454 measured 3.3s) that
+    // duplicate was half of the wait before a new tab could take a key.
+    //
+    // Nothing is lost by dropping it: the returned path was discarded, the
+    // failure is reported just as well through the route ack below, and the
+    // first-install consent question still reaches this process — the daemon
+    // runs its probe under `RouteSetup::blocking`, which installs the relay
+    // that turns the question into a frame on this very connection.
     let mut stream = connect()?;
     let ack = crate::daemon::router::negotiate(&mut stream, header)
         .map_err(|e| anyhow::anyhow!("route this pane to {}: {e}", header.describe()))?;