From e7b0a6a5e70ce463d1d13cbcc34c0f895b3d702a Mon Sep 17 00:00:00 2001
From: Joe Bryan <joemfb@gmail.com>
Date: Thu, 17 Oct 2019 14:19:21 -0700
Subject: [PATCH 1/4] u3: print the size of the free lists on |mass

---
 pkg/urbit/worker/main.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/pkg/urbit/worker/main.c b/pkg/urbit/worker/main.c
index 7d3f3474d9..5b9754bb07 100644
--- a/pkg/urbit/worker/main.c
+++ b/pkg/urbit/worker/main.c
@@ -306,6 +306,7 @@ _worker_grab(u3_noun sac, u3_noun ovo, u3_noun vir)
     tot_w += u3a_maid(fil_u, "effects", u3a_mark_noun(vir));
 
     u3a_print_memory(fil_u, "total marked", tot_w);
+    u3a_print_memory(fil_u, "free lists", u3a_idle(u3R));
     u3a_print_memory(fil_u, "sweep", u3a_sweep());
 
     fflush(fil_u);

From bf5a1276afab0c96db662030974138c227e55cb6 Mon Sep 17 00:00:00 2001
From: Joe Bryan <joemfb@gmail.com>
Date: Thu, 17 Oct 2019 15:50:04 -0700
Subject: [PATCH 2/4] u3: restore memory reclamation every 1k events

---
 pkg/urbit/worker/main.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/pkg/urbit/worker/main.c b/pkg/urbit/worker/main.c
index 5b9754bb07..67f8f4a2a0 100644
--- a/pkg/urbit/worker/main.c
+++ b/pkg/urbit/worker/main.c
@@ -606,6 +606,15 @@ _worker_work_live(c3_d evt_d, u3_noun job)
         rec_o = c3y;
         pri   = 0;
       }
+      //  reclaim memory from persistent caches periodically
+      //
+      //    XX this is a hack to work two things
+      //    - bytecode caches grow rapidly and can't be simply capped
+      //    - we don't make very effective use of our free lists
+      //
+      else {
+        rec_o = _(0 == (evt_d % 1000ULL));
+      }
 
       //  notify daemon of memory pressure via "fake" effect
       //

From 1cfedf227331d4df9aaec5cfdc27f50f1195e6f1 Mon Sep 17 00:00:00 2001
From: Joe Bryan <joemfb@gmail.com>
Date: Thu, 17 Oct 2019 15:50:28 -0700
Subject: [PATCH 3/4] u3: statically measure memory on startup if < 1/2 the
 loom is free

---
 pkg/urbit/worker/main.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/pkg/urbit/worker/main.c b/pkg/urbit/worker/main.c
index 67f8f4a2a0..28211c24ce 100644
--- a/pkg/urbit/worker/main.c
+++ b/pkg/urbit/worker/main.c
@@ -898,6 +898,21 @@ _worker_poke(void* vod_p, u3_noun mat)
   }
 }
 
+/* _worker_static_grab(): garbage collect, checking for profiling. RETAIN.
+*/
+static void
+_worker_static_grab(void)
+{
+  c3_assert( u3R == &(u3H->rod_u) );
+
+  fprintf(stderr, "work: measuring memory:\r\n");
+  u3a_print_memory(stderr, "total marked", u3m_mark(stderr));
+  u3a_print_memory(stderr, "free lists", u3a_idle(u3R));
+  u3a_print_memory(stderr, "sweep", u3a_sweep());
+  fprintf(stderr, "\r\n");
+  fflush(stderr);
+}
+
 /* u3_worker_boot(): send startup message to manager.
 */
 void
@@ -927,6 +942,18 @@ u3_worker_boot(void)
   u3l_log("work: play %" PRIu64 "\r\n", nex_d);
 
   _worker_send(u3nc(c3__play, dat));
+
+  //  measure/print static memory usage if < 1/2 of the loom is available
+  //
+  {
+    c3_w pen_w = u3a_open(u3R);
+
+    if ( !(pen_w > (1 << 28)) ) {
+      fprintf(stderr, "\r\n");
+      u3a_print_memory(stderr, "work: contiguous free space", pen_w);
+      _worker_static_grab();
+    }
+  }
 }
 
 /* main(): main() when run as urbit-worker

From 85a656471f64eff1faebbdc0ac54be590dce7942 Mon Sep 17 00:00:00 2001
From: Joe Bryan <joemfb@gmail.com>
Date: Thu, 17 Oct 2019 15:57:19 -0700
Subject: [PATCH 4/4] u3: removes "worker_send_replace" printf

---
 pkg/urbit/worker/main.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/pkg/urbit/worker/main.c b/pkg/urbit/worker/main.c
index 28211c24ce..b63c6c87dc 100644
--- a/pkg/urbit/worker/main.c
+++ b/pkg/urbit/worker/main.c
@@ -341,10 +341,6 @@ _worker_send(u3_noun job)
 static void
 _worker_send_replace(c3_d evt_d, u3_noun job)
 {
-  u3l_log("worker_send_replace %" PRIu64 " %s\r\n",
-          evt_d,
-          u3r_string(u3h(u3t(u3t(job)))));
-
   _worker_send(u3nt(c3__work,
                     u3i_chubs(1, &evt_d),
                     u3ke_jam(u3nc(u3V.mug_l, job))));