Changeset 140079 in webkit

Timestamp:

Jan 17, 2013 6:00:52 PM (11 years ago)

Author:

abarth@webkit.org

Message:

BackgroundHTMLParser should go 18% faster on html-parser-srcdoc benchmark
​https://bugs.webkit.org/show_bug.cgi?id=107201

Reviewed by Tony Gentilcore.

Prior to this patch, we would tokenize all the input before delivering
any tokens to the main thread. Effectively, that prevented the
background parser from running in parallel with the main thread.

This patch causes us to send tokens to the main thread periodically.
The constant in this patch is somewhat arbitrary. We'll need to tune it
later with more realistic workloads.

This patch improves the performance of the html-parser-srcdoc benchmark
by 18%. (This patch is based on Eric's work in
​https://github.com/tonygentilcore/webkit/commit/072331194520c7770b5e34baefbbbba948834971.)

• html/parser/BackgroundHTMLParser.cpp:

(WebCore):
(WebCore::BackgroundHTMLParser::pumpTokenizer):
(WebCore::BackgroundHTMLParser::sendTokensToMainThread):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• html/parser/BackgroundHTMLParser.cpp (modified) (3 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2013-01-17  Adam Barth  <abarth@webkit.org>
+
+        BackgroundHTMLParser should go 18% faster on html-parser-srcdoc benchmark
+        https://bugs.webkit.org/show_bug.cgi?id=107201
+
+        Reviewed by Tony Gentilcore.
+
+        Prior to this patch, we would tokenize all the input before delivering
+        any tokens to the main thread. Effectively, that prevented the
+        background parser from running in parallel with the main thread.
+
+        This patch causes us to send tokens to the main thread periodically.
+        The constant in this patch is somewhat arbitrary. We'll need to tune it
+        later with more realistic workloads.
+
+        This patch improves the performance of the html-parser-srcdoc benchmark
+        by 18%. (This patch is based on Eric's work in
+        https://github.com/tonygentilcore/webkit/commit/072331194520c7770b5e34baefbbbba948834971.)
+
+        * html/parser/BackgroundHTMLParser.cpp:
+        (WebCore):
+        (WebCore::BackgroundHTMLParser::pumpTokenizer):
+        (WebCore::BackgroundHTMLParser::sendTokensToMainThread):
+
 2013-01-17  Matt Falkenhagen  <falken@chromium.org>
 

trunk/Source/WebCore/html/parser/BackgroundHTMLParser.cpp

@@ -47 +47 @@
 
 #endif
+
+// FIXME: Tune this constant based on a benchmark. The current value was choosen arbitrarily.
+static const size_t pendingTokenLimit = 4000;
 
 typedef const void* ParserIdentifier;
@@ -158 +161 @@
         m_tokenizer->setShouldAllowCDATA(m_inForeignContent);
         m_token.clear();
-    }
-
-#ifndef NDEBUG
-    checkThatTokensAreSafeToSendToAnotherThread(m_pendingTokens);
-#endif
+
+        if (m_pendingTokens.size() >= pendingTokenLimit)
+            sendTokensToMainThread();
+    }
 
     sendTokensToMainThread();
@@ -200 +202 @@
 void BackgroundHTMLParser::sendTokensToMainThread()
 {
+    if (m_pendingTokens.isEmpty()) {
+        ASSERT(!m_isPausedWaitingForScripts);
+        return;
+    }
+
+#ifndef NDEBUG
+    checkThatTokensAreSafeToSendToAnotherThread(m_pendingTokens);
+#endif
+
     TokenDelivery* delivery = new TokenDelivery;
     delivery->identifier = m_parserIdentifer;