Add case with saturate memory

128M peak memory in a script

script/src/verify/tests/ckb_latest/features_since_v2023.rs

@@ -1320,3 +1320,9 @@ fn check_spawn_io_cycles() {
 
     assert_eq!(cycles2 - cycles1, offset_size / 2);
 }
+
+#[test]
+fn check_spawn_saturate_memory() {
+    let result = simple_spawn_test("testdata/spawn_saturate_memory", &[0]);
+    assert_eq!(result.is_ok(), SCRIPT_VERSION == ScriptVersion::V2);
+}

script/testdata/Makefile

@@ -74,7 +74,8 @@ ALL_BINS := jalr_zero \
             spawn_fuzzing \
             spawn_huge_swap \
             spawn_cycles \
-            spawn_io_cycles
+            spawn_io_cycles \
+            spawn_saturate_memory
 
 ALL_LIBS := is_even.lib \
             add1.lib sub1.lib mul2.lib div2.lib
@@ -162,3 +163,4 @@ spawn_fuzzing: spawn_fuzzing.c spawn_utils.h
 spawn_huge_swap: spawn_huge_swap.c spawn_utils.h
 spawn_cycles: spawn_cycles.c spawn_utils.h
 spawn_io_cycles: spawn_io_cycles.c spawn_utils.h
+spawn_saturate_memory: spawn_saturate_memory.c spawn_utils.h

script/testdata/spawn_saturate_memory.c

@@ -0,0 +1,45 @@
+#include "spawn_utils.h"
+
+#define MAX_MEMORY (4 * 1024 * 1024)
+#define PAGE_SIZE (4 * 1024)
+
+extern char _end[];
+
+void dirty_all_pages() {
+    uint64_t addr = (uint64_t)_end;
+    while (addr < MAX_MEMORY) {
+        uint8_t* ptr = (uint8_t*)addr;
+        *ptr = 0;
+        addr += PAGE_SIZE;
+    }
+}
+
+int main(int argc, const char* argv[]) {
+    int err = 0;
+    if (argc > 0) {
+        // child
+        dirty_all_pages();
+        uint64_t inherited_fds[2];
+        size_t inherited_fds_length = 2;
+        err = ckb_inherited_file_descriptors(inherited_fds, &inherited_fds_length);
+        uint64_t length = MAX_MEMORY;
+        // Write a piece of data starting from address 0 with a size of 4M.
+        // Internally, it is cached before being read out.
+        err = ckb_write(inherited_fds[CKB_STDOUT], 0, &length);
+        // should be blocked forever since there is no reading on other end
+        CHECK(err);
+    } else {
+        // parent
+        for (size_t i = 0; i < 15; i++) {
+            uint64_t pid = 0;
+            const char* argv[] = {"", 0};
+            uint64_t fds[2] = {0};
+            err = full_spawn(0, 1, argv, fds, &pid);
+            CHECK(err);
+        }
+        dirty_all_pages();
+    }
+
+exit:
+    return err;
+}