Added garbage collection counter, for pathological use cases.

icculus · Jul 7, 2009 · 2135bfc · 2135bfc
1 parent afd3ae9
commit 2135bfc
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Showing 3 changed files with 26 additions and 1 deletion.
diff --git a/lua_glue.c b/lua_glue.c
@@ -475,6 +475,11 @@ void MojoLua_collectGarbage(void)
     int pre = 0;
     int post = 0;
 
+    lua_getglobal(L, MOJOSETUP_NAMESPACE);
+    if (lua_istable(L, -1))  // namespace is sane?
+        set_integer(L, 0, "garbagecounter");
+    lua_pop(L, 1);
+
     pre = (lua_gc(L, LUA_GCCOUNT, 0) * 1024) + lua_gc(L, LUA_GCCOUNTB, 0);
     logDebug("Collecting garbage (currently using %0 bytes).", numstr(pre));
     ticks = MojoPlatform_ticks();
@@ -487,7 +492,8 @@ void MojoLua_collectGarbage(void)
 
 
 // You can trigger the garbage collector with more control in the standard
-//  Lua runtime, but this notes profiling and statistics via logDebug().
+//  Lua runtime, but this notes profiling and statistics via logDebug(),
+//  and resets MojoSetup.garbagecounter to zero.
 static int luahook_collectgarbage(lua_State *L)
 {
     MojoLua_collectGarbage();

diff --git a/scripts/mojosetup_init.lua b/scripts/mojosetup_init.lua
@@ -21,6 +21,24 @@
 
 local _ = MojoSetup.translate
 
+-- Set up the garbage counter. Things that are done in possibly long-running
+--  loops that create a lot of junk can optionally set a threshold and call
+--  MojoSetup.incrementgarbagecounter() on each iteration. Whenever you hit
+--  the threshold, garbage collection runs and resets the counter. This keeps
+--  memory usage from spiraling out of control for pathological cases.
+-- Note that the counter resets in MojoSetup.collectgarbage() itself, so you
+--  don't have to worry about the counter accumulating and firing off extra
+--  unnecessary collections if you happen to hit a loop at the wrong time.
+MojoSetup.garbagecounter = 0
+MojoSetup.garbagethreshold = 500
+
+function MojoSetup.incrementgarbagecount()
+    MojoSetup.garbagecounter = MojoSetup.garbagecounter + 1
+    if MojoSetup.garbagecounter >= MojoSetup.garbagethreshold then
+        MojoSetup.collectgarbage()
+    end
+end
+
 -- Returns three elements: protocol, host, path
 function MojoSetup.spliturl(url)
     return string.match(url, "^(.+://)(.-)/(.*)")

diff --git a/scripts/mojosetup_mainline.lua b/scripts/mojosetup_mainline.lua
@@ -419,6 +419,7 @@ local function install_file(dest, perms, writefn, desc, manifestkey)
     end
 
     MojoSetup.loginfo("Created file '" .. dest .. "'")
+    MojoSetup.incrementgarbagecount()
 end