feat: add ebpf_max_messages configuration

Author: swananan

config.toml

@@ -104,6 +104,17 @@ default_focus = "InteractiveCommand"
 # Default: [4, 3, 3]
 panel_ratios = [3, 3, 3]
 
+# Maximum number of eBPF trace messages to keep in the output panel
+# Older messages are automatically discarded when this limit is reached
+# Recommended values:
+#   - Low-frequency tracing: 1000-2000
+#   - Medium-frequency tracing: 2000-5000 (default: 2000)
+#   - High-frequency tracing: 5000-10000
+# Minimum value: 100
+# Note: Larger values consume more memory
+# Default: 2000
+ebpf_max_messages = 2000
+
 # Command history configuration
 [ui.history]
 # Enable/disable command history file functionality

docs/configuration.md

@@ -241,6 +241,16 @@ default_focus = "InteractiveCommand"
 # Must be 3 positive (non-zero) integers
 panel_ratios = [4, 3, 3]
 
+# Maximum number of eBPF trace messages to keep in the output panel
+# Older messages are automatically discarded when this limit is reached
+# Minimum value: 100
+# Recommended values:
+#   - Low-frequency tracing: 1000-2000
+#   - Medium-frequency tracing: 2000-5000 (default: 2000)
+#   - High-frequency tracing: 5000-10000
+# Note: Larger values consume more memory
+ebpf_max_messages = 2000
+
 [ui.history]
 # Enable command history
 enabled = true
@@ -422,6 +432,7 @@ export LLVM_SYS_170_PREFIX=/usr/lib/llvm-17
 - **Layout**: Horizontal (panels side by side)
 - **Panel Ratios**: 4:3:3 (Source:EbpfInfo:Command)
 - **Default Focus**: InteractiveCommand panel
+- **eBPF Max Messages**: 2000 messages
 - **History**: Enabled with 5000 entry limit
 
 ## File Output Naming
@@ -450,7 +461,9 @@ GhostScope validates configuration at startup:
 4. **Panel Ratios**: Ensures all 3 values are positive (non-zero) integers
 5. **Log Level**: Validates against allowed values (error, warn, info, debug, trace)
 6. **Layout Mode**: Validates against allowed values (Horizontal, Vertical - capitalized)
-7. **eBPF Configuration**:
+7. **UI Configuration**:
+   - **ebpf_max_messages**: Must be at least 100
+8. **eBPF Configuration**:
    - **ringbuf_size**: Must be power of 2, range 4096-16777216 bytes
    - **perf_page_count**: Must be power of 2, range 8-1024 pages
    - **proc_module_offsets_max_entries**: Must be in range 64-65536
@@ -468,6 +481,7 @@ Invalid configuration will produce clear error messages with suggestions for fix
 - **"perf_page_count must be a power of 2"**: Use values like 32, 64, 128, 256, etc.
 - **"perf_page_count X is out of reasonable range"**: Must be between 8 and 1024 pages.
 - **"proc_module_offsets_max_entries X is out of reasonable range"**: Must be between 64 and 65536.
+- **"ebpf_max_messages X is too small"**: Must be at least 100. Increase the value in your config file.
 
 ## Best Practices
 

docs/zh/configuration.md

@@ -240,6 +240,16 @@ default_focus = "InteractiveCommand"
 # 必须是 3 个正整数
 panel_ratios = [4, 3, 3]
 
+# eBPF 输出面板保留的最大跟踪消息数量
+# 超过限制时，旧消息会自动丢弃
+# 最小值：100
+# 推荐值：
+#   - 低频跟踪：1000-2000
+#   - 中频跟踪：2000-5000（默认：2000）
+#   - 高频跟踪：5000-10000
+# 注意：较大的值会消耗更多内存
+ebpf_max_messages = 2000
+
 [ui.history]
 # 启用命令历史
 enabled = true
@@ -421,6 +431,7 @@ export LLVM_SYS_170_PREFIX=/usr/lib/llvm-17
 - **布局**：Horizontal（面板横向排列）
 - **面板比例**：4:3:3（Source:EbpfInfo:Command）
 - **默认焦点**：InteractiveCommand 面板
+- **eBPF 最大消息数**：2000 条消息
 - **历史记录**：启用，5000 条条目限制
 
 ## 文件输出命名
@@ -449,7 +460,9 @@ GhostScope 在启动时验证配置：
 4. **面板比例**：确保所有 3 个值都是正（非零）整数
 5. **日志级别**：验证是否为允许的值（error, warn, info, debug, trace）
 6. **布局模式**：验证是否为允许的值（Horizontal, Vertical - 首字母大写）
-7. **eBPF 配置**：
+7. **UI 配置**：
+   - **ebpf_max_messages**：必须至少为 100
+8. **eBPF 配置**：
    - **ringbuf_size**：必须是 2 的幂，范围 4096-16777216 字节
    - **proc_module_offsets_max_entries**：必须在 64-65536 范围内
 
@@ -464,6 +477,7 @@ GhostScope 在启动时验证配置：
 - **"ringbuf_size must be a power of 2"**：使用 2 的幂值，如 131072、262144、524288 等。
 - **"ringbuf_size X is out of reasonable range"**：必须在 4KB 到 16MB 之间。
 - **"proc_module_offsets_max_entries X is out of reasonable range"**：必须在 64 到 65536 之间。
+- **"ebpf_max_messages X is too small"**：必须至少为 100。在配置文件中增加该值。
 
 ## 最佳实践
 

ghostscope-ui/src/lib.rs

@@ -21,6 +21,7 @@ pub async fn run_tui_mode(event_registry: EventRegistry, layout_mode: LayoutMode
         panel_ratios: [4, 3, 3], // Default ratios for backward compatibility
         default_focus: crate::action::PanelType::InteractiveCommand,
         history: HistoryConfig::default(),
+        ebpf_max_messages: 2000, // Default
     };
     run_tui_mode_with_config(event_registry, ui_config).await
 }

ghostscope-ui/src/model/app_state.rs

@@ -203,7 +203,7 @@ impl AppState {
             loading_state: LoadingState::Initializing, // Start with loading, wait for runtime response
             loading_ui: LoadingUI::new(),
             source_panel: SourcePanelState::new(),
-            ebpf_panel: EbpfPanelState::new(),
+            ebpf_panel: EbpfPanelState::new_with_max_messages(ui_config.ebpf_max_messages),
             command_panel: CommandPanelState::new_with_config(&ui_config.history),
             command_renderer: OptimizedRenderer::new(),
             command_input_handler: OptimizedInputHandler::new(),

ghostscope-ui/src/model/panel_state.rs

@@ -130,10 +130,14 @@ pub enum DisplayMode {
 
 impl EbpfPanelState {
     pub fn new() -> Self {
+        Self::new_with_max_messages(2000)
+    }
+
+    pub fn new_with_max_messages(max_messages: usize) -> Self {
         Self {
             trace_events: VecDeque::new(),
             scroll_offset: 0,
-            max_messages: 2000, // TODO: Make this configurable in the future
+            max_messages,
             auto_scroll: true,
             cursor_trace_index: 0,
             show_cursor: false,

ghostscope-ui/src/model/ui_state.rs

@@ -31,6 +31,7 @@ pub struct UiConfig {
     pub panel_ratios: [u16; 3], // [Source, EbpfInfo, InteractiveCommand]
     pub default_focus: crate::action::PanelType,
     pub history: HistoryConfig,
+    pub ebpf_max_messages: usize,
 }
 
 /// UI-specific state management
@@ -57,6 +58,7 @@ impl UIState {
             panel_ratios: [4, 3, 3], // Default ratios
             default_focus: crate::action::PanelType::InteractiveCommand,
             history: HistoryConfig::default(),
+            ebpf_max_messages: 2000, // Default value
         })
     }
 }

ghostscope/src/config/merged.rs

@@ -31,6 +31,7 @@ pub struct MergedConfig {
     pub panel_ratios: [u16; 3],
     pub history_enabled: bool,
     pub history_max_entries: usize,
+    pub ebpf_max_messages: usize,
 
     // DWARF configuration
     #[allow(dead_code)]
@@ -157,6 +158,7 @@ impl MergedConfig {
             panel_ratios: config.ui.panel_ratios, // UI config from file
             history_enabled: config.ui.history.enabled,
             history_max_entries: config.ui.history.max_entries,
+            ebpf_max_messages: config.ui.ebpf_max_messages,
             dwarf_search_paths: config.dwarf.search_paths,
             ebpf_config: {
                 // Command line --force-perf-event-array overrides config file
@@ -216,6 +218,7 @@ impl MergedConfig {
                 enabled: self.history_enabled,
                 max_entries: self.history_max_entries,
             },
+            ebpf_max_messages: self.ebpf_max_messages,
         }
     }
 

ghostscope/src/config/settings.rs

@@ -195,6 +195,9 @@ pub struct UiConfigToml {
     /// Command history configuration
     #[serde(default)]
     pub history: HistoryConfigToml,
+    /// Maximum number of eBPF trace messages to keep in the output panel
+    #[serde(default = "default_ebpf_max_messages")]
+    pub ebpf_max_messages: usize,
 }
 
 #[derive(Debug, Clone, Deserialize, Serialize)]
@@ -288,6 +291,10 @@ fn default_history_max_entries() -> usize {
     5000
 }
 
+fn default_ebpf_max_messages() -> usize {
+    2000
+}
+
 // Default implementations for each config section
 impl Default for GeneralConfig {
     fn default() -> Self {
@@ -414,7 +421,31 @@ impl Default for UiConfigToml {
             default_focus: PanelType::default(),
             panel_ratios: default_panel_ratios(),
             history: HistoryConfigToml::default(),
+            ebpf_max_messages: default_ebpf_max_messages(),
+        }
+    }
+}
+
+impl UiConfigToml {
+    /// Validate UI configuration values
+    pub fn validate(&self, file_path: &str) -> Result<()> {
+        // Validate ebpf_max_messages is reasonable (at least 100)
+        if self.ebpf_max_messages < 100 {
+            return Err(anyhow::anyhow!(
+                "❌ Invalid UI configuration in '{}':\n\n\
+                ebpf_max_messages {} is too small\n\n\
+                💡 Minimum value: 100\n\
+                Recommended values:\n\
+                  - Low-frequency tracing: 1000-2000\n\
+                  - Medium-frequency tracing: 2000-5000 (default: 2000)\n\
+                  - High-frequency tracing: 5000-10000\n\
+                Note: Larger values consume more memory",
+                file_path,
+                self.ebpf_max_messages
+            ));
         }
+
+        Ok(())
     }
 }
 
@@ -477,6 +508,9 @@ impl Config {
         // Validate eBPF configuration
         config.ebpf.validate(&path.display().to_string())?;
 
+        // Validate UI configuration
+        config.ui.validate(&path.display().to_string())?;
+
         Ok(config)
     }
 

ghostscope/src/runtime/coordinator.rs

@@ -56,6 +56,7 @@ pub async fn run_tui_coordinator(parsed_args: ParsedArgs) -> Result<()> {
         default_focus: ghostscope_ui::PanelType::InteractiveCommand, // Default
         panel_ratios: [4, 3, 3],                                     // Default
         history: ghostscope_ui::HistoryConfig::default(),
+        ebpf_max_messages: 2000, // Default
     };
 
     // Create a default MergedConfig from ParsedArgs for compatibility