Slow form submission

When I submit a form, I can see my b开发者_Python百科rowser's progress bar slowly increased, it takes 4-6s to submit a form. It was a generic form like :

<form id="someid" name="someName" action="someAction.do">
   ...
</form>

I test it in IE8 and Firefox 3,both are very slow. My network condition is fine, my server works great. What could be the problem?

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Your server-side code is slow.