Firefox and IE - slow forum server response

[lao ce]

Hi guys, here is my problem: Only on FF and IE the forum loading extremely slowly, every page, even the registration. On Chrome and even on Safari the forum pages are loading in a couple of seconds. On FF there is an 8 second waiting on the first server response. This is not too good... at all. This is a small forum, nothing extreme is going on, it should fly.

(I did read this: http://www.simplemachines.org/community/index.php?topic=293441.0
thank you)

forum.ovr-scca.org
SMF 1.1.19 / 2.0.6 Update
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Off-Topic_BBC_Tag    1.1.1.2         
Signature Settings Mod  1.1           

I could use some help, I don't even know what to check, where to go from here.

Thank you.

[kat]

I just visited http://forum.ovr-scca.org using Opera v12 x64, Firefox v28, PaleMoon v24.4.1 (An x64 version of Firefox), Opium v20 and IE 11 x64.

Opera and Opium loaded the page almost instantly. The Firefox ones were a little slower, as was IE.

Weird.

Have a look at Admin>Server settings. In there, try checking "Disable hostname lookups".

[lao ce]

I turned it off, I don't think there is any effect. It will be off for a while for testing purposes.

I contacted with my hosting company, they say that it is a software issue, since a "hello world" php runs fast on every browser. They have a point.
I cannot imagine what happens on the server side of every single forum page even the "static" ones (help, register etc) what is specific to IE and FF.

How can I debug this? (I should add: with limited php knowledge?)

[kat]

I'm not, entirely, sure that you can. Although Firefox and IE were noticeably slower than opera, they weren't what you'd call painfully slow. At least, they weren't, for me.

Who's your host, out of curiosity?

[lao ce]

Well, I measure 8 second server response waiting time on any page on FF. Right now it is 8900 milliseconds - waiting for nothing. On Chrome the page is coming without any noticeable waiting at all. I tested it from home and from my workplace as well.

We are with a small company, called CeraNet. Nice guys, local company.

So there is nothing what can be done here. It is pretty said. I feel that this should work well.

Thank you for your time!

[margarett]

There are some things really specific to IE, but it's all about layout and JS, not database-relevant.

Try to uncheck "Enable compressed output "

[kat]

Have you asked your host, about this, too?

[lao ce]

margarett - compressed output was and is unchecked.

K@
I've asked my host, they said since a "hello world" php file is running well on every browser the hosting environment is good.

They told me to debug the forum code until I find what slows down the forum.  Obviously I don't know what kind of browser specific code is running on the server side. I cannot even imagine why on earth a forum needs to run different code on every page depending on the browser. I have a hard time believing that this is the problem - but, it is possible.

[kat]

Odd... I just tried, again, with the same browsers. Although FF is quite a bit slower than Opera, it's not, quite, terrible. It's certainly a bit quicker than it was, last time.

Have you changed anything?