Q: System Freezes Randomly after 10.6.3 Update

FWIW, when the WindowServer process gets "stuck" it is sometimes because some third party addition to the system is interfering with its normal operation. Because it is crucial to the implementation of so many system services, any interference with its normal operation can affect system stability in unexpected ways. Unfortunately, several common third party add-ons in effect do that, including ones that are not its direct descendants (child processes), making it difficult to tell what is actually causing it to hang.

Typically, a safe boot prevents these add-ons from starting up, so that is a fairly good indicator of this kind of problem, although it isn't much help in pinning the cause down to any one process.

For those curious about the intricate details of the WindowServer process, this section of the "Daemons & Agents" developer document may be of interest, if for no other reason than the several references to behaviors "lost in the depths of history" & the warnings about changes in future releases of Mac OS X that may help explain the reasons why OS updates sometimes "break" things that worked in previous versions.

I, too, experienced the freeze-ups after upgrading to 10.6.3. I have an iMac8,1; Intel Core 2 Duo; 2.8 GHz; ATI Radeon HD 2600 Pro. The system was rock solid on Leopard and Snow Leopard through 10.6.2. Five days after upgrading to 10.6.3 (in April), the system would freeze, mouse & keyboard unresponsive, sometimes the screen would go dark, sometimes the screen would go gray with thin vertical white lines, sometimes the screen would remain as-is. Power off/on was the only way to regain control. I re-installed 10.6.2 and haven't had any freezes in 7 weeks. I'm interested in hearing if 10.6.4 fixes this. On several freezes I ended up with corrupt files that I was working on at the time of the freeze, so I'm hesitant to move off of 10.6.2. Thanks to everyone that has posted their 10.6.4 results. Please keep us informed.

RC-R,

Please, don't confuse matters any more by continuing to insist that this was not as much as system problem as anything else because by following your logic, many people may spend unnecessary time reinstalling their systems only to find the problems reappearing...

I know you disagree with my conclusions, but here they are for reference by others:

http://discussions.apple.com/thread.jspa?messageID=11663560#11663560

The bottom line, however, is that I would strongly suggest that anyone still seeing "freezing" problems with 10.6.3 (as well as anyone who has waited before updating or who has rolled back to 10.5.8 or to 10.6.2 or to whatever) should simply bite the bullet and try the 10.6.4 Combo Update.

If you are still having issues at that point, I would suggest an erase/install to 10.6.4 is in order... and if problems persist at the point, a trip to either an Apple Store or an Apple qualified shop for a hardware checkout along the lines of my experience.

Good Luck...

I'm going to take the "if it ain't broke don't fix it" path.

If 10.6.2 works well for you stick with it, especially if 10.6.3 caused you issues.

I had horrible freeze problems with 10.6.3 and went back to 10.6.2, In a month of 10.6.2 I experienced one freeze day before yesterday, compared to five-six a day on 10.6.3. Another problem with 10.6.3 was random horizontal lines appearing in Mail and Safari windows, which the downgrade also cured. When the lines appeared TechTool would identify "Bad VRAM" which also disappeared after the downgrade.

Yesterday I installed the 10.6.4 Combo (not Software Update). After Restart the lines appeared again. I repaired permissions, restarted and zapped the PRAM. Since then everything is functioning normally, no lines, no freezes. I'll let you all know if the problems recur.

Show me a single instance where rolling back to 10.6.2 did not fix the mouse/trackpad freeze problem. I am not talking about the the whole computer freezing problem.

jimmdean:

I would probably agree if my iMac were not still under an Apple Care contract because it should accept all these incremental updates to the operating system... and if the hardware is eventually at fault, Apple will repair it.

napabill:

I hope your experience with 10.6.4 continues to be incident-free; for what it's worth, following an update or when testing a kext, I often run the full cleanup with Onyx that clears the kernel cache amongst other things... and I run "du -sx /" with adminstrator permissions almost every day because it cleans up lingering swap file nodes before calculating actual disk usage (it's a side effect that also returns some inactive memory to the "free" state... try it with the Activity Monitor and you'll see for yourself. It's possible that fixing permissions does this, too...).

I'm quite interested to see if your machine is still running well after a few days... Good Luck.

batondor wrote:
I hope your experience with 10.6.4 continues to be incident-free; for what it's worth, following an update or when testing a kext, I often run the full cleanup with Onyx that clears the kernel cache amongst other things... and I run "du -sx /" with adminstrator permissions almost every day because it cleans up lingering swap file nodes before calculating actual disk usage (it's a side effect that also returns some inactive memory to the "free" state... try it with the Activity Monitor and you'll see for yourself. It's possible that fixing permissions does this, too...).

Not sure why you're concerned about the amount of free memory vs. inactive? All you're doing here is slowing the system down: once to calculate the disk usage, and once again when OS X has to reload information from disk which it was keeping 'just in case' in the inactive memory pool.

e.g. see http://support.apple.com/kb/ht1342

Cheers

Message was edited by: Tom Robinson5

Sorry, I just got carried away when explaining that "du -sx /" is a simple "trick" that cleans up system caches... and while it is true that running it does slow the system down while it's running, which can take a few minutes, because I've noticed that it seems to be worth it when "free" memory goes to zero...

My real intent, however, was to attempt to understand what changed for "napabill" when he "cleaned up" by repairing permissions in his system running 10.6.4 and the problems lingering from 10.6.3 seemingly disappeared...

Well unlike you guys I haven't experienced this until tonight.

I posted this an hour ago:
"No idea, but just now I had to restart my 24" iMac 2.8GHz C2D running 10.6.4 by holding the power button just like you. The screen all of a sudden started flickering black horizontal lines like mad for about 4 minutes. I could move my mouse for about the first two minutes but clicks and the keyboard wouldn't register.

Then everything froze, the screen stopped flickering but showed the entire screen in tact, and connected devices like external hard drives and iPod Touch powered down as if the computer turned off. I used the power button to shutdown after 5 minutes of nothing happening.

I've noticed the screen flicker three times now while I've been typing this... =/ "

Since then I haven't had any flickers though.

I'm a first time poster as I've never really had a problem with any of my previous Macs before however since updating Snow Leopard on my iMac 3.06 with the Nvidia GeForce 8800 card I have had 48 hours of crashes and beach balls while trying to restore then eventually scrub my hard disk before being able to restore back to version 10.5.8 from an external drive through Time Machine.

I too thought this must be hardware however since going back to 10.5.8 I have my 'good' iMac back again and I can get on with my work! I have been crash free for the past 24 hours.

Can Apple please provide some advice around what to do as I do not want to take the risk again going back to 10.6....?

Raccc & Fizzybhoy,

What make, model & type (firewire or USB) external drive?
Does it have the latest firmware installed?
Are the manufacturers drivers installed (if required)?

Not sure what the external hard drive has to do with this but it's a Fantom Drive connected direct through USB. I've had it for 2 years at least. All it did was spin down because it thought the computer went to sleep or shut down. My iPod did the same.

I haven't had any flickers since the three I mentioned so hopefully everything is ok now.

Thrasher91604 wrote:
Show me a single instance where rolling back to 10.6.2 did not fix the mouse/trackpad freeze problem. I am not talking about the the whole computer freezing problem.

I have no idea what you mean about the difference between a mouse/trackpad freeze & a "whole computer" one. Do you mean by "whole computer" mouse plus keyboard or something else?

Anyway, the point is not if going back to 10.6.2 fixes anything but if there is a way to get 10.6.3 to work without any freezing issues after seeing them when the update was initially applied. Some users have been successful at this; some have not. Some have not even been able to get 10.6.2 to work without freezes & have gone back to some version of 10.5.

It should be obvious from this that not all the freezing problems have the same cause.

batondor wrote:
Please, don't confuse matters any more by continuing to insist that this was not as much as system problem as anything else because by following your logic, many people may spend unnecessary time reinstalling their systems only to find the problems reappearing…

And some may find their problems do disappear after a reinstall, or that even after updating to 10.6.4 now that it is available a reinstall is still necessary to set things right.

What confuses matters the most is to assume that all the freezing problems must have the same cause, since it leads to the conclusion that what does or doesn't work for one user also will or won't for all the others.

Judging from your comment about what to do if issues remain after updating to 10.6.4, we seem to agree on that, at least to some extent. Where we differ the most is if it is worth the time to try to resolve the issues with 10.6.3 before updating to 10.6.4 or not.

If you browse through the historic advice/opinions in any of the "Installation and Setup" forums about trying to resolve existing issues simply by updating the OS to a later version, I think you will see that the general (but admittedly far from unanimous) consensus is that it is not recommended. There is a good reason for this: since the preexisting OS is updating itself, if it is misbehaving to begin with then the chances are high that the update will not go as expected. (It is much like a demented doctor trying to perform surgery on himself.) The problems this causes are not always immediately evident. The worst case scenario results in data loss, possibly even to backups attached to the system, so it is something that should be taken seriously.

I understand that it is a chore to try to track down the source of the problem, especially knowing that it might be fruitless & that it is very tempting just to apply the latest update & hope for the best, but it is clearly not true that "it ain't broke" to begin with -- if that was true then there would be no problems -- so it does need to be fixed. And since it is the *operating system*, which controls everything the computer does, it doesn't make a lot of sense to gamble with half-way measures.