diff --git a/runtime/include/sandbox.h b/runtime/include/sandbox.h
index 5a2974d..dcad022 100644
--- a/runtime/include/sandbox.h
+++ b/runtime/include/sandbox.h
@@ -279,3 +279,4 @@ sandbox_print_perf(struct sandbox *sandbox)
 
 void sandbox_set_as_initialized(struct sandbox *sandbox, struct sandbox_request *sandbox_request,
                                 uint64_t allocation_timestamp);
+void sandbox_set_as_runnable(struct sandbox *sandbox);
diff --git a/runtime/src/local_runqueue_minheap.c b/runtime/src/local_runqueue_minheap.c
index ec11f64..e252823 100644
--- a/runtime/src/local_runqueue_minheap.c
+++ b/runtime/src/local_runqueue_minheap.c
@@ -93,8 +93,8 @@ local_runqueue_minheap_get_next()
 		sandbox = sandbox_allocate(sandbox_request);
 		if (!sandbox) goto sandbox_allocate_err;
 
-		sandbox->state = SANDBOX_RUNNABLE;
-		local_runqueue_minheap_add(sandbox);
+		sandbox_set_as_runnable(sandbox);
+
 	} else if (sandbox_rc == -2) {
 		/* Unable to take lock, so just return NULL and try later */
 		assert(sandbox == NULL);
@@ -157,8 +157,7 @@ local_runqueue_minheap_preempt(ucontext_t *user_context)
 		if (!next_sandbox) goto err_sandbox_allocate;
 
 		/* Set as runnable and add it to the runqueue */
-		next_sandbox->state = SANDBOX_RUNNABLE;
-		local_runqueue_add(next_sandbox);
+		sandbox_set_as_runnable(next_sandbox);
 
 		/* Save the context of the currently executing sandbox before switching from it */
 		arch_mcontext_save(&current_sandbox->ctxt, &user_context->uc_mcontext);
diff --git a/runtime/src/sandbox.c b/runtime/src/sandbox.c
index 5149245..3c5083c 100644
--- a/runtime/src/sandbox.c
+++ b/runtime/src/sandbox.c
@@ -7,6 +7,7 @@
 #include "current_sandbox.h"
 #include "http_parser_settings.h"
 #include "libuv_callbacks.h"
+#include "local_runqueue.h"
 #include "panic.h"
 #include "runtime.h"
 #include "sandbox.h"
@@ -528,6 +529,49 @@ sandbox_set_as_initialized(struct sandbox *sandbox, struct sandbox_request *sand
 	sandbox->state = SANDBOX_INITIALIZED;
 }
 
+/**
+ * Transitions a sandbox to the SANDBOX_RUNNABLE state.
+ *
+ * This occurs in the following scenarios:
+ * - A sandbox in the SANDBOX_INITIALIZED state completes initialization and is ready to be run
+ * - A sandbox in the SANDBOX_BLOCKED state completes what was blocking it and is ready to be run
+ * - A sandbox in the SANDBOX_RUNNING state is preempted before competion and is ready to be run
+ *
+ * @param sandbox
+ **/
+void
+sandbox_set_as_runnable(struct sandbox *sandbox)
+{
+	assert(sandbox);
+	assert(sandbox->last_state_change_timestamp > 0);
+	uint64_t        now                    = __getcycles();
+	uint64_t        duration_of_last_state = now - sandbox->last_state_change_timestamp;
+	sandbox_state_t last_state             = sandbox->state;
+	sandbox->state                         = SANDBOX_SET_AS_RUNNABLE;
+	debuglog("Thread %lu | Sandbox %lu | %s => Runnable\n", pthread_self(), sandbox->allocation_timestamp,
+	         sandbox_state_stringify(last_state));
+
+	switch (last_state) {
+	case SANDBOX_INITIALIZED: {
+		sandbox->initializing_duration += duration_of_last_state;
+		local_runqueue_add(sandbox);
+		break;
+	}
+	case SANDBOX_BLOCKED: {
+		sandbox->blocked_duration += duration_of_last_state;
+		local_runqueue_add(sandbox);
+		break;
+	}
+	default: {
+		panic("Thread %lu | Sandbox %lu | Illegal transition from %s to Runnable\n", pthread_self(),
+		      sandbox->allocation_timestamp, sandbox_state_stringify(last_state));
+	}
+	}
+
+	sandbox->last_state_change_timestamp = now;
+	sandbox->state                       = SANDBOX_RUNNABLE;
+}
+
 
 /**
  * Allocates a new sandbox from a sandbox request
diff --git a/runtime/src/worker_thread.c b/runtime/src/worker_thread.c
index e3ae20b..49d789c 100644
--- a/runtime/src/worker_thread.c
+++ b/runtime/src/worker_thread.c
@@ -116,12 +116,7 @@ worker_thread_wakeup_sandbox(struct sandbox *sandbox)
 	assert(sandbox->state == SANDBOX_BLOCKED);
 
 	software_interrupt_disable();
-
-	sandbox->state = SANDBOX_RUNNABLE;
-	debuglog("Marking blocked sandbox as runnable\n");
-	local_runqueue_add(sandbox);
-
-done:
+	sandbox_set_as_runnable(sandbox);
 	software_interrupt_enable();
 }