diff --git a/aos/linux_code/init.cc b/aos/linux_code/init.cc
new file mode 100644
index 0000000..3c0704e
--- /dev/null
+++ b/aos/linux_code/init.cc
@@ -0,0 +1,115 @@
+#include "aos/linux_code/init.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <errno.h>
+#include <sched.h>
+#include <sys/resource.h>
+#include <asm-generic/resource.h>  // for RLIMIT_RTTIME
+#include <sys/types.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+#include "aos/common/die.h"
+#include "aos/linux_code/logging/linux_logging.h"
+#include "aos/linux_code/ipc_lib/shared_mem.h"
+
+namespace aos {
+
+namespace {
+
+void SetSoftRLimit(int resource, rlim64_t soft, bool set_for_root) {
+  bool am_root = getuid() == 0;
+  if (set_for_root || !am_root) {
+    struct rlimit64 rlim;
+    if (getrlimit64(resource, &rlim) == -1) {
+      Die("%s-init: getrlimit64(%d) failed with %d (%s)\n",
+          program_invocation_short_name, resource, errno, strerror(errno));
+    }
+    rlim.rlim_cur = soft;
+    if (setrlimit64(resource, &rlim) == -1) {
+      Die("%s-init: setrlimit64(%d, {cur=%ju,max=%ju})"
+          " failed with %d (%s)\n", program_invocation_short_name,
+          resource, (uintmax_t)rlim.rlim_cur, (uintmax_t)rlim.rlim_max,
+          errno, strerror(errno));
+    }
+  }
+}
+
+// Common stuff that needs to happen at the beginning of both the realtime and
+// non-realtime initialization sequences. May be called twice.
+void InitStart() {
+  // Allow locking as much as we want into RAM.
+  SetSoftRLimit(RLIMIT_MEMLOCK, RLIM_INFINITY, false);
+
+  // Do create core files of unlimited size.
+  SetSoftRLimit(RLIMIT_CORE, RLIM_INFINITY, true);
+}
+
+int LockAllMemory() {
+  InitStart();
+  if (mlockall(MCL_CURRENT | MCL_FUTURE) == -1) {
+    Die("%s-init: mlockall failed with %d (%s)\n",
+        program_invocation_short_name, errno, strerror(errno));
+  }
+
+  // Forces the memory pages for all the stack space that we're ever going to
+  // use to be loaded into memory (so it can be locked there).
+  uint8_t data[4096 * 8];
+  // Not 0 because linux might optimize that to a 0-filled page.
+  memset(data, 1, sizeof(data));
+
+  return 0;
+}
+
+// Do the initialization code that is necessary for both realtime and
+// non-realtime processes.
+void DoInitNRT(aos_core_create create) {
+  InitStart();
+  if (aos_core_create_shared_mem(create)) {
+    Die("%s-init: creating shared memory reference failed\n",
+        program_invocation_short_name);
+  }
+  logging::linux_code::Register();
+}
+
+const char *const kNoRealtimeEnvironmentVariable = "AOS_NO_REALTIME";
+
+}  // namespace
+
+void InitNRT() { DoInitNRT(aos_core_create::reference); }
+void InitCreate() { DoInitNRT(aos_core_create::create); }
+void Init(int relative_priority) {
+  if (getenv(kNoRealtimeEnvironmentVariable) == NULL) {  // if nobody set it
+    LockAllMemory();
+    // Only let rt processes run for 1 second straight.
+    SetSoftRLimit(RLIMIT_RTTIME, 1000000, true);
+    // Allow rt processes up to priority 40.
+    SetSoftRLimit(RLIMIT_RTPRIO, 40, false);
+    // Set our process to priority 40.
+    struct sched_param param;
+    param.sched_priority = 30 + relative_priority;
+    if (sched_setscheduler(0, SCHED_FIFO, &param) != 0) {
+      Die("%s-init: setting SCHED_FIFO failed with %d (%s)\n",
+          program_invocation_short_name, errno, strerror(errno));
+    }
+  } else {
+    fprintf(stderr, "%s not doing realtime initialization because environment"
+            " variable %s is set\n", program_invocation_short_name,
+            kNoRealtimeEnvironmentVariable);
+    printf("no realtime for %s. see stderr\n", program_invocation_short_name);
+  }
+
+  InitNRT();
+}
+
+void Cleanup() {
+  if (aos_core_free_shared_mem()) {
+    Die("%s-init: freeing shared mem failed\n",
+        program_invocation_short_name);
+  }
+}
+
+}  // namespace aos