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I am experiencing extremely slow Javascript performance under CentOS across all browsers I have tried. It is to the point that for sites that make heavy use of javascript (such as this one) that my CPU is maxed out for several seconds, and I have to wait for whatever rendering is being performed, making these sites almost unusable. Using the same set of browsers/versions under Windows XP and Ubuntu 6.06 as well as 8.04 on the same machine does not cause any issues. It is to the point that I am trying obscure browsers in hopes that I will find one without issue, but I have not found one that does not suffer the same javascript issues.

The browsers I've tried are:

  1. Firefox 3.0.15 from the CentOS 5.4 repositories
  2. Opera 10.01 installed via rpm from the Opera webiste
  3. Conkeror 0.9.1 installed via source

The only explanation is that there is some shared library they all use for running javascript as it would explain why every browser I've tried has the same problem, but I can't seem to find anything online stating that this is a known issue. Does anyone have any suggestions/ideas for how I can go about pinpointing the source of the issue and/or resolving it?

Note: I am experiencing the problem on a work machine which needs to run CentOS so switching to Ubuntu which I normally run at home can not be considered.

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Konqueror? – scunliffe Dec 9 '09 at 3:32
up vote 1 down vote accepted

Could it be a graphics issue on the machine? If X is using a completely accelerated driver because the installer didn't know the right one to select (or simply doesn't have one) for your graphics hardware you might see this sort of behaviour as the browser reflows the page during updates.

Though if this is the case I would expect every application to show visible signs of slow performance, not just browsers (though browsers tend to update their display repeatedly while content it loading/updated so they are likely more obviously affected than other apps).

It is worth checking to see what driver your X setup is using and (if it isn't using the right one already) trying to install a better one. This might involve installing a proprietary (binary only) driver.

share|improve this answer
This is on my work computer so for the most part I'm only using emacs and a shell to do programming (not very graphics intensive). Now that you've pointed it out, I'm noticing that there is a good second delay when alt-tabbing and my email client is slow, though all of this pales in comparison to the browser issue. I'm looking into my graphics driver now. – Mark Roddy Dec 9 '09 at 21:19
Installed and configured the proprietary video driver (which wasn't easy), and now everything in the browser is smooth. Thanks for your help! – Mark Roddy Dec 9 '09 at 22:17

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