perf: set static mmap threshold on gnu target env by default

src/app/mod.rs

@@ -138,7 +138,11 @@ pub(crate) fn iced_settings<App: Application>(
 ///
 /// Returns error on application failure.
 pub fn run<App: Application>(settings: Settings, flags: App::Flags) -> iced::Result {
-    let default_font = settings.default_font;
+    #[cfg(target_env = "gnu")]
+    if let Some(threshold) = settings.default_mmap_threshold {
+        crate::malloc::limit_mmap_threshold(threshold);
+    }
+
     let (settings, mut flags, window_settings) = iced_settings::<App>(settings, flags);
     #[cfg(not(feature = "multi-window"))]
     {

src/app/settings.rs

@@ -38,6 +38,9 @@ pub struct Settings {
     /// Default size of fonts.
     pub(crate) default_text_size: f32,
 
+    /// Set the default mmap threshold for malloc with mallopt.
+    pub(crate) default_mmap_threshold: Option<i32>,
+
     /// Whether the window should be resizable or not.
     /// and the size of the window border which can be dragged for a resize
     pub(crate) resizable: Option<f64>,
@@ -85,6 +88,7 @@ impl Default for Settings {
             default_font: font::default(),
             default_icon_theme: None,
             default_text_size: 14.0,
+            default_mmap_threshold: Some(128 * 1024),
             resizable: Some(8.0),
             scale_factor: std::env::var("COSMIC_SCALE")
                 .ok()