Varnish is our new forcefield
After extensive testing of various caching techniques, we have just enabled additional level of pages caching for anonymous users. We are using Varnish to do the hard job, keeping Lighttpd serving Wikidot pages for logged-in users.
Pages are cached for 3 minutes, and subsequent requests of the same URL to our backend service (based on PHP FastCGI processes) are queued in order to improve overall stability and performance.
Caching is applied only is the following conditions are met:
- it's a wiki page (not uploaded file, login screen, AJAX requests etc)
- user does not have session cookie set (this basically means users that are not logged in)
- page is accessed with http, not https
This all assures logged in users always get the current version of page, while anonymous traffic may get page outdated by about 3 minutes. Disabling caching of https traffic means there should be no problem in creating account and logging in.
If you encounter any problems with Wikidot (especially when browsing as anonymous user) and you think it might be due the additional caching of content, please let us know at moc.todikiw|troppus#moc.todikiw|troppus.
The significant improvement is that Wikidot can handle traffic spikes much better now. In the past we have seen many sites getting enormous traffic from social sites (like Twitter or Digg) over short periods of time. From now on such traffic spikes will no longer impair performance and availability of other Wikidot sites. Thanks to Varnish, our new shield :-D
Sounds like this would prevent the Snow Leopard scenario… so what would happen if an anonymous user goes to edit the page?
Editing a page is maintained through AJAX, though it ain't gonna be cached at all. Everything is going to work as usual.
Recently (today since one hour back) I am facing problem while editing one of my wiki site, http://ancientvoice.wikidot.com. I am able to see the content without logging in (ie browsing as an anonymous user). But when I log in and try to edit my content I get the following error:-
Ancient Voice wiki is under mainenance - we will be back soon!
Error 503 Service Unavailable
Guru Meditation:
XID: 1319931046
Varnish
I am not seeing the web-site pages and if try to load any page of my site I get this error and nothing else.
This error is coming for almost an hour. What is going on? Please resolve this as fast as possible.
I am not facing any problem for my other wiki-dot websites and they are working perfectly fine.
[[html]]
<a target="_blank" href="http://feeds.feedburner.com/~r/AncientVoice-forum-posts/~6/1"><img src="http://feeds.feedburner.com/AncientVoice-forum-posts.1.gif" alt="AncientVoice - forum posts" style="border:0"></a>
[[/html]]
Sorry for the inconvenience. Please check if editing works for you now.
Piotr Gabryjeluk
visit my blog
Now it is working fine. Thanks.
[[html]]
<a target="_blank" href="http://feeds.feedburner.com/~r/AncientVoice-forum-posts/~6/1"><img src="http://feeds.feedburner.com/AncientVoice-forum-posts.1.gif" alt="AncientVoice - forum posts" style="border:0"></a>
[[/html]]
According to my google webmaster tools, the time it takes to download a page on WikiWealth.com went from about 1 second to anywhere from 2.5 to 5 seconds per page. I assume it had to do with the caching changes, because it all started around June 20th.
I hope that whatever is causing the spike in download time settles out in time. I just wanted to bring it to your attention if it's something that other Wikidot users experience.
Thank you.
WikiWealth.com - Stock, Fund, Commodity & Currency Research | SWOT Analysis, WACC
Hi,
could you confirm the longer loading times by other metrics or tools?
We are constantly working on performance — today we have deployed cache optimization and will be adding more servers today or tomorrow. So if there are longer loading times, they should get back to previous values or even lower.
Michał Frąckowiak @ Wikidot Inc.
Visit my blog at michalf.me
Hello Michal,
I only noticed the slow performance while I was using the site. Google webmaster tools confirmed my observation, but I haven't checked with any other tools.
Everything is already working better, so I'm sure that Google will show the improvement in the response speeds as soon as google updates their info.
Thanks for the updates. Dave
WikiWealth.com - Stock, Fund, Commodity & Currency Research | SWOT Analysis, WACC
@Wiki Wealth: your website is really awesome … and useful.
Hello Michal, The performance of my site immediately improved after you made the last optimization upgrades. Thank you. Pages load even faster than better!
The Error: I use google gadgets to implement a stock chart on each of my pages. This chart is programed to change per the stock on each page. When I pull up one of my research pages, the google gadgets shows the same stock chart on all of my pages even though the symbol is coded differently. A week ago, the charts would all match the stock symbol found at the top of the page, but now, they all show the same symbol. Below is the example of the chart code. The "Symbol=AAPL" part is different per each page / chart.
Issue: After the cache optimization went through, different pages on WikiWealth started showing a problems with my google gadgets. This problem spread to all my research, but neither the gadget creator or myself can figure it out. I assumed this relates to the optimization upgrade you mentioned. Either something is generating incorrect gadget code (per an upgrade) or it's not updating because of the optimization.
See for example:
1. http://www.wikiwealth.com/research:aapl
2. http://www.wikiwealth.com/research:ko
3. http://www.wikiwealth.com/research:goog
My charts all display MSFT for microsoft, but other users have QQQQ no matter the page they visit.
Questions: Are the google gadgets rendering correctly? Is this related to the upgrades? Is the error temporary?
Thank you, Dave
WikiWealth.com - Stock, Fund, Commodity & Currency Research | SWOT Analysis, WACC
Ignore my response above. It was a google gadget problem and they just fixed it. Sorry for the confusion.
WikiWealth.com - Stock, Fund, Commodity & Currency Research | SWOT Analysis, WACC