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terrybkk

Windows XP Lock Up

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I can paste email into Spamcop and it is parsed without a problem but when I hit the button to send the spam reports my computer comes to a near halt. I am using Netscape 7.1 and Windows XP Professional. Windows task manager shows 100%cpu usage and vsmon.exe using 99% of it.

Any ideas?

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Yeah, vsmon.exe... I've got some history with that file...

We're running the Grub client from Grub.org (a distributed crawler for indexing websites for WiseNut and LookSmart). It absolutely kills ZoneAlarm.

The reason for this:

ZoneAlarm is a stateful packet inspection firewall, meaning that it checks each incoming packet to see if a corresponding outgoing packet was sent to request the incoming packet. If there is, the incoming packet is allowed in. If not, it's blocked.

The problem is that ZoneAlarm is designed for extremely light-weight use. It's lookup table is small, and the code that parses through the lookup table is inefficient and has a small memory leak.

Thus, for any application that creates a high number of simultaneous or concurrent connections, the lookup table is quickly filled, causing ZoneAlarm to crash. This usually causes the computer to lock up. When the lookup table starts filling up, the computer will bog down first.

With Grub running, ZoneAlarm only lasted an hour before crashing. So, I had to shut down ZoneAlarm and restart it to clear out the lookup table and recover the lost memory from the memory leak on a regular basis.

I eventually dumped ZA and started using WinXP's ICF. It's much more robust, and has taken everything I've thrown at it (including 100 new connections per second for an extended period of time).

So, when your computer starts bogging down, start up Task Manager and look at the ZoneAlarm files... you'll see them hogging a bunch of memory and CPU.

Shut down ZA, wait 15 seconds for the memory to be flushed, and restart it. That'll fix things temporarily.

ZoneLabs knows about the problem (it exists in all versions of ZA), but has decided that it's more expedient to forego fixing the code and continue shipping defective software.

Amazingly, the same problem exists in most consumer-oriented stateful packet inspection firewalls... so, before you plunk down your hard-earned money, go to Grub.org and fire up the GrubClient for a while to test the firewall's robustness.

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