Changeset 277388 in webkit

Timestamp:

May 12, 2021, 2:06:35 PM (5 years ago)

Author:

ggaren@apple.com

Message:

ConservativeRoots triggers page demand on Speedometer
​https://bugs.webkit.org/show_bug.cgi?id=225676

Reviewed by Filip Pizlo.

Use a 2048 item / 16kB inline buffer. That's about 10% bigger than the
max capacity observed on Speedometer, and small enough to reasonably fit
on the stack.

Removed the separate out of line capacity because it was smaller than
the new inline capacity.

• heap/ConservativeRoots.cpp:

(JSC::ConservativeRoots::grow):

• heap/ConservativeRoots.h:

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• heap/ConservativeRoots.cpp (modified) (1 diff)
• heap/ConservativeRoots.h (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2021-05-12  Geoffrey Garen  <ggaren@apple.com>
+
+        ConservativeRoots triggers page demand on Speedometer
+        https://bugs.webkit.org/show_bug.cgi?id=225676
+
+        Reviewed by Filip Pizlo.
+
+        Use a 2048 item / 16kB inline buffer. That's about 10% bigger than the
+        max capacity observed on Speedometer, and small enough to reasonably fit
+        on the stack.
+
+        Removed the separate out of line capacity because it was smaller than
+        the new inline capacity.
+
+        * heap/ConservativeRoots.cpp:
+        (JSC::ConservativeRoots::grow):
+        * heap/ConservativeRoots.h:
+
 2021-05-12  Mark Lam  <mark.lam@apple.com>
 

trunk/Source/JavaScriptCore/heap/ConservativeRoots.cpp

@@ -54 +54 @@
 void ConservativeRoots::grow()
 {
-    size_t newCapacity = m_capacity == inlineCapacity ? nonInlineCapacity : m_capacity * 2;
+    size_t newCapacity = m_capacity * 2;
     HeapCell** newRoots = static_cast<HeapCell**>(OSAllocator::reserveAndCommit(newCapacity * sizeof(HeapCell*)));
     memcpy(newRoots, m_roots, m_size * sizeof(HeapCell*));

trunk/Source/JavaScriptCore/heap/ConservativeRoots.h

@@ -46 +46 @@
 
 private:
-    static constexpr size_t inlineCapacity = 128;
-    static constexpr size_t nonInlineCapacity = 8192 / sizeof(HeapCell*);
+    static constexpr size_t inlineCapacity = 2048;
     
     template<typename MarkHook>