598393 - Minimize Cookie IPC messages

Status: RESOLVED DUPLICATE of bug 558624

(Core :: IPC, defect)

Description

[Alon Zakai (:azakai)]

Loading www.mozilla.org in Fennec, we have 46 sendings of

  PCookieServiceParent::Msg_GetCookieString

which is sync, and causes 0.0463 seconds of latency. The cookies are send by:

17: nsContentUtils::LoadImage ==> HttpChannelChild::AsyncOpen
10: nsHtml5TreeOpExecutor::PreloadImage ==> HttpChannelChild::AsyncOpen
10: JS ==> nsIDOMHTMLDocument_GetCookie ==> nsHTMLDocument::GetCookie
5: nsHtml5TreeOpExecutor::PreloadScript ==> HttpChannelChild::AsyncOpen
2: nsDocument::PreloadStyle ==> HttpChannelChild::AsyncOpen
1: nsDocShell::LoadURI ==> HttpChannelChild::AsyncOpen
1: nsImageLoadingContent::LoadImage ==> HttpChannelChild::AsyncOpen

Numbers are how many occurrences there are. On other websites this can of course be worse, for example on icanhascheezburger.com we have 474 messages and 0.3184 seconds of latency.

So, the majority are caused by AsyncOpen calls, specifically

#2  0x00007f5cae5cb9ef in mozilla::net::HttpBaseChannel::AddCookiesToRequest (this=0x7f5c95d24430)
    at /home/alon/Dev/mozilla-central/netwerk/protocol/http/HttpBaseChannel.cpp:1257
#3  0x00007f5cae5f23aa in mozilla::net::HttpChannelChild::AsyncOpen (this=0x7f5c95d24400, listener=0x7f5c95d202c0, aContext=0x0)
    at /home/alon/Dev/mozilla-central/netwerk/protocol/http/HttpChannelChild.cpp:861

Basically, each AsyncOpen wants a cookie. We should investigate whether there is a way to minimize these, perhaps some are not needed, and/or perhaps they can be async and not sync.