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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Hi,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Could it not be set that a there is a maximum execution time for
any workers that are still active, definable by the browser but with a
suggested value of say 1000milliseconds in the spec, any processing that takes
longer than this is killed, but gives the option for well built scripts and
cleanup processes to run gracefully.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Martin<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span
style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> whatwg-bounces@lists.whatwg.org
[mailto:whatwg-bounces@lists.whatwg.org] <b>On Behalf Of </b>Robert O'Callahan<br>
<b>Sent:</b> 08 August 2008 23:30<br>
<b>To:</b> Jonas Sicking<br>
<b>Cc:</b> whatwg<br>
<b>Subject:</b> Re: [whatwg] Active workers when user leaves the page<o:p></o:p></span></p>
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<p class=MsoNormal><o:p> </o:p></p>
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<p class=MsoNormal>On Sat, Aug 9, 2008 at 7:01 AM, Jonas Sicking
<jonas@sicking.cc> wrote:<o:p></o:p></p>
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<p class=MsoNormal>I do want to be agressive with killing workers when the user
leaves a page since that makes for better user experience. However I'm also worried
about stopping scripts halfway through breaking things and leaving the site
with half-finished operations that are stored in databases or localStorage.<o:p></o:p></p>
</blockquote>
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<p class=MsoNormal><br>
Aggressive killing of workers without warning when the user navigates away
would actually be a good feature.<br>
<br>
There are various reasons outside anyone's control that a worker might die
abruptly. For example, power failure, browser crash, or "slow-script"
style timeout. Applications need to be able to handle those cases, for example
by using database transactions or careful use of atomic operations. But that's
hard to test and authors probably won't design or test well for those cases
since they're relatively uncommon. Expanding abrupt termination scenarios to
include navigate-away makes abrupt termination much easier to test, forces
authors to design for it early, and will ultimately simplify the application
design by reducing the different ways a worker can terminate.<br>
<br>
This may sound a bit radical, but it's not a new idea. It's a principle
sometimes called "crash-only software". See e.g. <a
href="http://www.usenix.org/events/hotos03/tech/full_papers/candea/candea_html/">http://www.usenix.org/events/hotos03/tech/full_papers/candea/candea_html/</a><o:p></o:p></p>
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<p class=MsoNormal><br clear=all>
Rob<br>
-- <br>
"He was pierced for our transgressions, he was crushed for our iniquities;
the punishment that brought us peace was upon him, and by his wounds we are
healed. We all, like sheep, have gone astray, each of us has turned to his own
way; and the LORD has laid on him the iniquity of us all." [Isaiah 53:5-6]<o:p></o:p></p>
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<p class=MsoNormal><br>
-- <br>
This message has been scanned for viruses and <br>
dangerous content by <a href="http://www.mailscanner.info/"><b>MailScanner</b></a>,
and is <br>
believed to be clean. <o:p></o:p></p>
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