diff --git a/src/gui.rs b/src/gui.rs
index d9e7940..56be3d1 100644
--- a/src/gui.rs
+++ b/src/gui.rs
@@ -2619,7 +2619,23 @@ impl AcceleratorApp {
     }
 
     fn ensure_launcher_viewport(&self, ctx: &egui::Context) {
+        // Re-issuing these commands every frame makes winit emit resize events
+        // every frame, which marks the UI dirty and keeps egui repainting at
+        // full speed. Only send them when the window size actually drifted.
         let size = launcher_window_size();
+        let current = ctx.input(|input| {
+            input
+                .viewport()
+                .inner_rect
+                .map(|rect| rect.size())
+        });
+        let drifted = match current {
+            Some(current) => (current - size).length() > 1.0,
+            None => true,
+        };
+        if !drifted {
+            return;
+        }
         ctx.send_viewport_cmd(egui::ViewportCommand::InnerSize(size));
         ctx.send_viewport_cmd(egui::ViewportCommand::MinInnerSize(size));
         ctx.send_viewport_cmd(egui::ViewportCommand::MaxInnerSize(size));
diff --git a/src/platform.rs b/src/platform.rs
index 17aee8c..0e5f0bb 100644
--- a/src/platform.rs
+++ b/src/platform.rs
@@ -257,31 +257,59 @@ pub fn is_process_running(pid: u32) -> bool {
 
     let kill_probe = Command::new("kill").args(["-0", &pid.to_string()]).output();
 
-    match kill_probe {
-        Ok(output) if output.status.success() => {
-            // Process exists — but check if it's a zombie (already dead, just
-            // waiting for the parent to reap it).  Treat zombies as "not running"
-            // so that stop/cleanup can proceed without waiting for a kill timeout.
-            is_unix_zombie(pid)
-        }
+    let exists = match kill_probe {
+        Ok(output) if output.status.success() => true,
         Ok(output) => {
             let stderr = String::from_utf8_lossy(&output.stderr);
             if stderr.contains("Operation not permitted") {
-                // Can't signal the process but it exists; still check zombie state.
-                return !is_unix_zombie(pid);
+                // Can't signal the process but it exists.
+                true
+            } else {
+                Command::new("ps")
+                    .args(["-p", &pid.to_string(), "-o", "pid="])
+                    .output()
+                    .ok()
+                    .map(|ps| {
+                        ps.status.success()
+                            && !String::from_utf8_lossy(&ps.stdout).trim().is_empty()
+                    })
+                    .unwrap_or(false)
             }
-
-            Command::new("ps")
-                .args(["-p", &pid.to_string(), "-o", "pid="])
-                .output()
-                .ok()
-                .map(|ps| {
-                    ps.status.success() && !String::from_utf8_lossy(&ps.stdout).trim().is_empty()
-                })
-                .unwrap_or(false)
         }
         Err(_) => false,
+    };
+    if !exists {
+        return false;
     }
+
+    // Process exists — but check if it's a zombie (already dead, just
+    // waiting for the parent to reap it).  Treat zombies as "not running"
+    // so that stop/cleanup can proceed without waiting for a kill timeout.
+    if is_unix_zombie(pid) {
+        return false;
+    }
+
+    unix_process_is_ours(pid)
+}
+
+/// Verify the pid actually belongs to this application. After a reboot a
+/// stale pid file often points at a recycled pid owned by an unrelated
+/// process (system daemons get the low pids first), which previously made
+/// `state::refresh` resurrect a phantom "running" state and the GUI skip
+/// the autostart.
+#[cfg(unix)]
+fn unix_process_is_ours(pid: u32) -> bool {
+    Command::new("ps")
+        .args(["-p", &pid.to_string(), "-o", "comm="])
+        .output()
+        .ok()
+        .map(|out| {
+            // Linux truncates comm to 15 chars ("linuxdo-acceler"); match the
+            // shared prefix so macOS full paths and Linux comms both pass.
+            let comm = String::from_utf8_lossy(&out.stdout).to_ascii_lowercase();
+            comm.contains("linuxdo-acceler")
+        })
+        .unwrap_or(false)
 }
 
 /// Check if a process is a zombie (defunct) on Unix.
diff --git a/src/runtime_log.rs b/src/runtime_log.rs
index 1731d38..e5d5b8c 100644
--- a/src/runtime_log.rs
+++ b/src/runtime_log.rs
@@ -1,5 +1,5 @@
 use std::fs::{self, OpenOptions};
-use std::io::Write;
+use std::io::{Read, Seek, SeekFrom, Write};
 use std::time::{SystemTime, UNIX_EPOCH};
 
 use anyhow::{Context, Result, anyhow};
@@ -7,12 +7,24 @@ use anyhow::{Context, Result, anyhow};
 use crate::paths::AppPaths;
 use crate::platform::sync_user_ownership;
 
+/// Rotate operations.log before it grows unbounded (a few months of proxy
+/// traffic was observed reaching >100MB, which the UI then re-read on every
+/// refresh). Keep one previous generation next to the active file.
+const MAX_LOG_SIZE: u64 = 8 * 1024 * 1024;
+
 pub(crate) fn append(paths: &AppPaths, level: &str, action: &str, message: &str) -> Result<()> {
     if let Some(parent) = paths.runtime_log_path.parent() {
         fs::create_dir_all(parent)
             .with_context(|| format!("failed to create {}", parent.display()))?;
     }
 
+    if let Ok(metadata) = fs::metadata(&paths.runtime_log_path) {
+        if metadata.len() >= MAX_LOG_SIZE {
+            let rotated = paths.runtime_log_path.with_extension("log.1");
+            let _ = fs::rename(&paths.runtime_log_path, rotated);
+        }
+    }
+
     let mut file = OpenOptions::new()
         .create(true)
         .append(true)
@@ -39,10 +51,29 @@ pub(crate) fn read_recent_lines(paths: &AppPaths, max_lines: usize) -> Result<Ve
         return Ok(Vec::new());
     }
 
-    let content = fs::read_to_string(&paths.runtime_log_path)
-        .with_context(|| format!("failed to read {}", paths.runtime_log_path.display()))?;
-    let mut lines = content
+    // operations.log grows without bound while the proxy runs; reading the
+    // whole file (observed at >100MB) on every UI refresh burns noticeable
+    // CPU. Seek to the tail and parse only a fixed window instead.
+    const TAIL_WINDOW: u64 = 64 * 1024;
+
+    let mut file = fs::File::open(&paths.runtime_log_path)
+        .with_context(|| format!("failed to open {}", paths.runtime_log_path.display()))?;
+    let size = file.metadata()?.len();
+    let window = size.min(TAIL_WINDOW);
+    let start = size - window;
+
+    file.seek(SeekFrom::Start(start))?;
+    let mut buf = vec![0u8; window as usize];
+    file.read_exact(&mut buf)
+        .with_context(|| format!("failed to read tail of {}", paths.runtime_log_path.display()))?;
+
+    let text = String::from_utf8_lossy(&buf);
+    // When the window starts mid-file the first line is likely a partial
+    // entry left over at the seek boundary, so skip it.
+    let skip_first = usize::from(start > 0);
+    let mut lines = text
         .lines()
+        .skip(skip_first)
         .map(str::trim)
         .filter(|line| !line.is_empty())
         .map(ToOwned::to_owned)
diff --git a/src/service.rs b/src/service.rs
index b34b8b0..3c998e5 100644
--- a/src/service.rs
+++ b/src/service.rs
@@ -278,6 +278,18 @@ pub fn run_privileged_helper(config_path: Option<PathBuf>) -> Result<()> {
         "特权辅助守护进程启动，开始监听 socket",
     );
 
+    // After a reboot the previous session's state files survive. This helper
+    // has not started any proxy yet, so a leftover "running" state is always
+    // stale; reconcile it before the GUI reads it, otherwise the GUI's
+    // autostart sees a phantom running state and never starts acceleration.
+    if let Err(error) = state::refresh(&paths) {
+        log_error(
+            &paths,
+            "privileged-helper",
+            &format!("清理残留服务状态失败: {error:#}"),
+        );
+    }
+
     // Shared state: holds the running proxy's shutdown channel and join handle.
     let proxy_state: Arc<Mutex<Option<ProxyHandle>>> = Arc::new(Mutex::new(None));
     let socket = helper_ipc::socket_path();