NetworkResourceLoadSchedulerMac.mm   [plain text]

/*
 * Copyright (C) 2012 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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#import "config.h"
#import "NetworkResourceLoadScheduler.h"

#import <WebCore/ResourceRequest.h>
#import <WebCore/ResourceRequestCFNet.h>
#import <WebCore/WebCoreSystemInterface.h>
#import <WebKitSystemInterface.h>

#if ENABLE(NETWORK_PROCESS)

using namespace WebCore;

namespace WebKit {

void NetworkResourceLoadScheduler::platformInitializeMaximumHTTPConnectionCountPerHost()
{
    wkInitializeMaximumHTTPConnectionCountPerHost = WKInitializeMaximumHTTPConnectionCountPerHost;
    wkSetHTTPPipeliningMaximumPriority = WKSetHTTPPipeliningMaximumPriority;
    wkSetHTTPPipeliningMinimumFastLanePriority = WKSetHTTPPipeliningMinimumFastLanePriority;

    // Our preferred connection-per-host limit is the standard 6, but we need to let CFNetwork handle a 7th
    // in case a synchronous XHRs is made while 6 loads are already outstanding.
    static const unsigned preferredConnectionCount = 7;
    static const unsigned unlimitedConnectionCount = 10000;

    // Always set the connection count per host, even when pipelining.
    unsigned maximumHTTPConnectionCountPerHost = wkInitializeMaximumHTTPConnectionCountPerHost(preferredConnectionCount);

    Boolean keyExistsAndHasValidFormat = false;
    Boolean prefValue = CFPreferencesGetAppBooleanValue(CFSTR("WebKitEnableHTTPPipelining"), kCFPreferencesCurrentApplication, &keyExistsAndHasValidFormat);
    
    if (keyExistsAndHasValidFormat)
        ResourceRequest::setHTTPPipeliningEnabled(prefValue);

    if (ResourceRequest::httpPipeliningEnabled()) {
        wkSetHTTPPipeliningMaximumPriority(toHTTPPipeliningPriority(ResourceLoadPriorityHighest));
        wkSetHTTPPipeliningMinimumFastLanePriority(toHTTPPipeliningPriority(ResourceLoadPriorityMedium));

        // When pipelining do not rate-limit requests sent from WebCore since CFNetwork handles that.
        m_maxRequestsInFlightPerHost = unlimitedConnectionCount;

        return;
    }

    // We've asked for one more connection per host than we intend to use in most cases so synch XHRs can bypass that limit.
    m_maxRequestsInFlightPerHost = maximumHTTPConnectionCountPerHost - 1;
}

} // namespace WebKit

#endif // ENABLE(NETWORK_PROCESS)