From 14f7a6075537031fe39d42c94ffbaa0582cd4069 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Wed, 24 Apr 2019 13:46:34 +0200
Subject: [PATCH] Keep some stats

---
 src/libexpr/gc.cc | 7 ++++++-
 src/libexpr/gc.hh | 4 ++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/libexpr/gc.cc b/src/libexpr/gc.cc
index 1a56ac324..2ed5e0198 100644
--- a/src/libexpr/gc.cc
+++ b/src/libexpr/gc.cc
@@ -44,7 +44,10 @@ GC::GC()
 
 GC::~GC()
 {
-    debug("allocated %d bytes in total", totalSize * WORD_SIZE);
+    printInfo("%d bytes in arenas, %d bytes allocated, %d bytes reclaimed by GC",
+        totalSize * WORD_SIZE,
+        allTimeWordsAllocated * WORD_SIZE,
+        allTimeWordsFreed * WORD_SIZE);
 
     size_t n = 0;
     for (Ptr<Object> * p = frontPtrSentinel->next; p != backPtrSentinel; p = p->next)
@@ -250,6 +253,8 @@ void GC::gc()
 
     debug("freed %d bytes in %d dead objects, keeping %d objects",
         totalWordsFreed * WORD_SIZE, totalObjectsFreed, marked);
+
+    allTimeWordsFreed += totalWordsFreed;
 }
 
 std::pair<size_t, size_t> GC::freeUnmarked(Arena & arena)
diff --git a/src/libexpr/gc.hh b/src/libexpr/gc.hh
index 5a62fb052..47edfd003 100644
--- a/src/libexpr/gc.hh
+++ b/src/libexpr/gc.hh
@@ -188,6 +188,9 @@ private:
 
     std::array<FreeList, 8> freeLists;
 
+    size_t allTimeWordsAllocated = 0;
+    size_t allTimeWordsFreed = 0;
+
     Object * allocObject(size_t size)
     {
         assert(size >= 2);
@@ -255,6 +258,7 @@ public:
     Ptr<T> alloc(size_t size, const Args & ... args)
     {
         auto raw = allocObject(size);
+        allTimeWordsAllocated += size;
         return new (raw) T(args...);
     }