I usually only get it if I have a comment reply open for a long time before clicking add. Feels like the continuation lasts for about 20 minutes.
There's no set timeout. They're kept in a queue.
Poll: Unknown or expired link on YC
11–20 of 37 posts
Re: Poll: Unknown or expired link on YC
#12It usually isn't a big deal, because the fix -go back, copy, refresh the page, paste- is trivial. For a less technical audience, this would be absolutely unacceptable. Are there elegant solutions to fix this? Could someone link the explanation to how the continuation sessions work, please?
I believe the specific code has to do with "fnid harvesting". See the comments here: http://github.com/nex3/arc/tree/master/srv.arc line 330 or so.
The general idea is described here: http://dresese.thehyatts.net/archives/000253.html
pg's original patent on this scheme: http://www.freepatentsonline.com/6205469.html
Re: Poll: Unknown or expired link on YC
#13I usually only get it if I have a comment reply open for a long time before clicking add. Feels like the continuation lasts for about 20 minutes.
There's no set timeout. They're kept in a queue.
With the load going up so much (causing the crashes) it also means the links expire faster. I would guess in under 10 minutes sometimes, maybe under 5.
Re: Poll: Unknown or expired link on YC
#14It usually isn't a big deal, because the fix -go back, copy, refresh the page, paste- is trivial. For a less technical audience, this would be absolutely unacceptable. Are there elegant solutions to fix this? Could someone link the explanation to how the continuation sessions work, please?
Explanation: http://pagesperso-systeme.lip6.fr/Christian.Queinnec/PDF/www...
A possible elegant solution is suggested in the paper: store the continuation on the client. I don't know what problems this presents in practice.
Re: Poll: Unknown or expired link on YC
#15It usually isn't a big deal, because the fix -go back, copy, refresh the page, paste- is trivial. For a less technical audience, this would be absolutely unacceptable. Are there elegant solutions to fix this? Could someone link the explanation to how the continuation sessions work, please?
Explanation: http://pagesperso-systeme.lip6.fr/Christian.Queinnec/PDF/www... A possible elegant solution is suggested in the paper: store the continuation on the client. I don't know what problems this presents in practice.
With GET requests, you frequently run into URL size issues. IE has a roughly 1800 character limit, which is pretty easy to hit with machine-generated data. I remember going through hell with JSF charting frameworks, trying to squeeze the serialized data down under 1800 characters. Eventually we gave up, pulled everything out of the serialized data (it still took up over 1K though, just through framework metadata, and so only left us around 500-800 bytes to play with), and threw it into query parameters that we could control ourselves.
This isn't an issue with POST, but then you run into the normal POST issues with refreshability, bookmarkability, and portable URLs.
Re: Poll: Unknown or expired link on YC
#16I see it a lot when I get down to the 5th page or so. Yes, I am really a nub with nothing better to do than hope that there is a 6th or 7th page of submissions on here :-) I really can't get enough of this site.
Re: Poll: Unknown or expired link on YC
#17I frequently get interrupted while writing comments and finish them a few minutes later, so I get bitten by this all the time.
Re: Poll: Unknown or expired link on YC
#18I read a lot, but I've only really noticed it when posting comments. I've got it maybe 3 times over the past week or two... which I guess is a lot, since I don't comment that often.
Re: Poll: Unknown or expired link on YC
#19Almost every time I write a comment I get this error.
update: Including this time.
Re: Poll: Unknown or expired link on YC
#20Earlier quoted context omitted.
Pretty sure that's what pg's said it is. Personally, that's way too short, as I'll leave threads open for half a day without reading it, then can't comment. I don't see any fundamental reason why continuations have to expire so fast.
Because they take up ram on the server. 20 minutes is standard session timeout for most session based web frameworks.
I wonder - would it be technically feasible to page the continuations out to temporary files on the server? Kind of like cookies, but on the server instead of the client!