browser sluggish, address resolution failing
 

Something weird is going on with my browsers, esp Opera but FireFox too. The first thing I noticed is slow response. Now it has gotten to a DNS failure. The really bad news is that I can avoid the problem by login into Windows; the problem is unique to Linux. I have cleared cookies, relogged, rebooted, and am running out of ideas. Except for the browsers, everything seems to be working well.

Slackware64 14.1 on HP i5-core machine, cable (no wifi) internet

Check the output of "ifconfig -a" for TX packets being much higher than RX packets. I've seen some boxes get hacked by Chinese recently and used as part of a DDOS attack.

Interesting. But what does one do about such things? And for that matter, what about viruses in general. There are lots of antivirus applications for Windows but I haven't noticed any for Linux.

I've never seen a virus on Linux although I did get the Lion worm back in the day. Intrusions can happen due to not patching one of the many recent vulnerabilities and not having a good firewall setup.

That is both reassuring and ominous. I am a programmer, not an administrator and I have no idea what is vulnerable. I depend on a router to be my firewall. Mostly I depend on the fact that there is nothing to be gained by messing with my systems. I might have found something though. I discovered that ghostery wasn't blocking ALL the cookies, new ones have been slipped in on me. I just fixed that but it's too early to say whether that will help. But it is ridiculous waiting while the browser times out trying to reach a site that I know is there. It's as bad as trying to get customer support from the cable company.

If there's trouble with the DNS server, that's got to be your ISP, not you. I had a horrible day last month when I couldn't download the whole of some sites, could ping but not download others, and couldn't even ping a few. The phone line of the ISP told me that due to heavy demand, waiting time for an advisor would be around 20 minutes! I gave up and next day all was back to normal. Things happen :banghead:

I was talking to my son and he mentioned new features in HTML5 which use storage on the client machine. That makes me wonder if that's the problem, that management of those persistent storage records is bogging. I don't really know anything about it, he says it Javascript stuff.

Wow, that's pretty bad.

That's what - one of the things - a distro is for. Somewhere, there is a 'security team' (even if that's actually a person and its not his full time job). Security makes mitigated (against whatever vulns have been discovered) apps available and your job is to get them installed in a timely fashion.

If you don't do your job, things will go bad sooner or later. If they don't do their job, things will probably go wrong faster (in the every install of 'vulnerable distro' will be exploitable, and some person with evil intent will try to take advantage).

Not really reliable. They do have problems from time to time and no one (relatively) installs patches... And they aren't the most configurable things in the world, in that even the ones that are based on a decent firewall are a bit 'dumbed down', to stop the UI putting the average user off.

Of course, that's probably wrong. If someone wants to recruit a machine for a botnet, then you are probably are a better target than many. And, anyway, the bad guys don't know what's there until they break in, so, one of the things that is there is the information about what is there. And some people will just want to break in for the hell of it and to prove that they can. So, for them, there is a bit of an ego boost available.

I'd have to guess no, because I don't see cookies as being particularly fundamental to the problem.

Well, there's ClamAV, but it is most use as a way of scanning files that might be passed on to windows boxes. But if you feel naked without some kind of AV application, then you might as well... Really, while there is malware for Linux, there aren't really viruses in the wild, so, to put it the other way, there is Linux malware (essentially) none of it is caught by an anti-virus app, because it isn't composed of viruses.

@smallpond
An interesting idea, but it is a rather long shot.

@rdx
AFAIK, windows ignores the rules on lookup expiration times, in order to speed things up, but has risks as well (this may not be true for recent versions of windows, I'm not sure). You might find that Chrome/Chromium do better, because it has a setting to pre-fetch DNS lookups, which could work here. Anyway, the first thing to do is to measure something; dig is your friend here.

Assuming that your DNS lookup time is poor, which seems like a good guess, then the next question is why. It might be overloading on your network, or it might just be that the DNS server that you are hooked up to is overloaded (...and that's quite often the case with the cheaper ISPs...apparently it is not the kind of thing that they see as a positive discriminator so often they can't run a nameserver to save their lives...).

It might then be a question of hooking up to a DNS server that works. Or you could run, eg, Dnsmasq to cache look-ups.

Ultimately the cure is to 1. kill plasma-desktop, 2. kill X, then restart a new X session (startx). It seems plasma-desktop and browsers get in a weird state where the browser hogs the CPU.