feat: expose systemMemoryInfo API for main worker

crates/sb_core/js/main_worker.js

@@ -1,6 +1,6 @@
-import { SUPABASE_USER_WORKERS } from "ext:sb_user_workers/user_workers.js";
-import { applySupabaseTag } from "ext:sb_core_main_js/js/http.js";
-import { core } from "ext:core/mod.js";
+import { SUPABASE_USER_WORKERS } from 'ext:sb_user_workers/user_workers.js';
+import { applySupabaseTag } from 'ext:sb_core_main_js/js/http.js';
+import { core } from 'ext:core/mod.js';
 
 const ops = core.ops;
 
@@ -10,6 +10,7 @@ Object.defineProperty(globalThis, 'EdgeRuntime', {
 			userWorkers: SUPABASE_USER_WORKERS,
 			getRuntimeMetrics: () => /* async */ ops.op_runtime_metrics(),
 			applySupabaseTag: (src, dest) => applySupabaseTag(src, dest),
+			systemMemoryInfo: () => ops.op_system_memory_info(),
 		};
 	},
 	configurable: true,

crates/sb_os/lib.rs

@@ -1,5 +1,57 @@
+use deno_core::op2;
 use std::collections::HashMap;
 
 pub type EnvVars = HashMap<String, String>;
 
-deno_core::extension!(sb_os, esm_entry_point = "ext:sb_os/os.js", esm = ["os.js"]);
+#[derive(serde::Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct MemInfo {
+    pub total: u64,
+    pub free: u64,
+    pub available: u64,
+    pub buffers: u64,
+    pub cached: u64,
+    pub swap_total: u64,
+    pub swap_free: u64,
+}
+
+#[op2]
+#[serde]
+fn op_system_memory_info() -> Option<MemInfo> {
+    let mut mem_info = MemInfo {
+        total: 0,
+        free: 0,
+        available: 0,
+        buffers: 0,
+        cached: 0,
+        swap_total: 0,
+        swap_free: 0,
+    };
+
+    #[cfg(any(target_os = "android", target_os = "linux"))]
+    {
+        let mut info = std::mem::MaybeUninit::uninit();
+        // SAFETY: `info` is a valid pointer to a `libc::sysinfo` struct.
+        let res = unsafe { libc::sysinfo(info.as_mut_ptr()) };
+        if res == 0 {
+            // SAFETY: `sysinfo` initializes the struct.
+            let info = unsafe { info.assume_init() };
+            let mem_unit = info.mem_unit as u64;
+            mem_info.swap_total = info.totalswap * mem_unit;
+            mem_info.swap_free = info.freeswap * mem_unit;
+            mem_info.total = info.totalram * mem_unit;
+            mem_info.free = info.freeram * mem_unit;
+            mem_info.available = mem_info.free;
+            mem_info.buffers = info.bufferram * mem_unit;
+        }
+    }
+
+    Some(mem_info)
+}
+
+deno_core::extension!(
+    sb_os,
+    ops = [op_system_memory_info],
+    esm_entry_point = "ext:sb_os/os.js",
+    esm = ["os.js"]
+);

examples/main/index.ts

@@ -1,11 +1,14 @@
 // @ts-ignore
-import { STATUS_CODE } from "https://deno.land/std/http/status.ts";
+import { STATUS_CODE } from 'https://deno.land/std/http/status.ts';
 
 console.log('main function started');
 
+// log system memory usage every 30s
+// setInterval(() => console.log(EdgeRuntime.systemMemoryInfo()), 30 * 1000);
+
 Deno.serve(async (req: Request) => {
 	const headers = new Headers({
-		"Content-Type": "application/json"
+		'Content-Type': 'application/json',
 	});
 
 	const url = new URL(req.url);
@@ -17,7 +20,7 @@ Deno.serve(async (req: Request) => {
 			JSON.stringify({ 'message': 'ok' }),
 			{
 				status: STATUS_CODE.OK,
-				headers
+				headers,
 			},
 		);
 	}
@@ -128,7 +131,7 @@ Deno.serve(async (req: Request) => {
 			console.error(e);
 
 			if (e instanceof Deno.errors.WorkerRequestCancelled) {
-				headers.append("Connection", "close");
+				headers.append('Connection', 'close');
 
 				// XXX(Nyannyacha): I can't think right now how to re-poll
 				// inside the worker pool without exposing the error to the
@@ -150,7 +153,7 @@ Deno.serve(async (req: Request) => {
 				JSON.stringify(error),
 				{
 					status: STATUS_CODE.InternalServerError,
-					headers
+					headers,
 				},
 			);
 		}