Filed under: Hardware, Airport, iMac, Troubleshooting
Workaround for the 27 inch iMac Flash lag?
We've had a few users tell us about performance lags that they're experiencing with their brand new 27" iMacs. Our own Casey Johnston even wrote a quick article about the problem last month. Now that everyone has had a few days to play with the issue and try the obligatory troubleshooting steps, we've been tipped about a possible solution.One of our readers claims that this isn't just related to Flash playback... it's possible that this lag problem is consistent across the system. Flash taxes your system more than most applications so it would show the lag problem more consistently than another application -- thus making it look like a problem only with Flash.
The suggestion at this point: cycle your wireless connection. By turning AirPort off and on again, some people are seeing the computer regain responsiveness. Obviously this isn't a permanent fix because the issue will most likely appear again after you reboot your machine... we can't say if the fix will persist for the entire session, either; the problem could come back before reboot.
Fellow TUAW blogger Joachim Bean suggests that the issues may be something related to PCI Express. Both the AirPort and graphics card are using PCI Express to communicate with the system. There's a possibility that the lines of communication are crossing during use. I'm still betting on a software issue -- at least, let's hope for that.
Let us know if this helps, or any other possible solutions you might have in the comments.
Thanks, Simon!
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Reader Comments (Page 1 of 2)
Spammerboy said 5:14PM on 11-03-2009
Do you think this problem is only on the dual core or also on the to be released quad core versions of the 27 inch iMac? I wonder. When playing flash though on my MacBook (Unibody June 2009), I also notice the CPU load going way over 100%. So nothing new there. Hopefully it is a software thing...
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Neil said 7:01PM on 11-03-2009
Ever since upgrading to snow leopard, my Macbook Pro suffers from terrible lag occasionally, usually when doing something graphics intensive (like working in Aperture). I'm also wondering if this is more of a snow leopard issue than an iMac issue.
Seth said 12:18AM on 11-05-2009
Hell I have a year-old 2.4Ghz Macbook that chokes on Flash. I thought it was a general Mac issue.
skalpa said 5:14PM on 11-03-2009
But wasn't the problem due to this "shit that Flash is" whatever ?
Whatever people can think of features my Mac still runs the most poorly tested O.S available.
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netkas said 5:29PM on 11-03-2009
My suggestion is - wlan shares irq (interrup line) with another
device(it can be anything, hdd/sound/etc), this might cause osx to
react wrong on interruption caused by wlan.
Jesse said 6:51PM on 11-03-2009
@netkas - irqs don't really work like that anymore, each pci bus has four interrupt lanes which are shared by peripherals (that's glossing it over -- but you get the point). Sharing and routing is handled automatically by modern PCI controllers and OSes; the old days of "irq sharing" are over.
The way that modern PCI works is a vast improvement over the old scheme, so that "interrupt sharing" is both the norm and highly stable.
drbrady said 5:27PM on 11-03-2009
Appreciate the follow-up on this issue. Hope you continue to follow it until resolved.
Was going to buy a 27" imac and new macbook. WILL NOT purchase until I see a resolution to this matter.
Quite disappointed in Apple for their lack of regard for creativity and consideration of users in their support. See it as a truly weak link since I switched back to mac a couple of years ago.
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netkas said 5:24PM on 11-03-2009
>Fellow TUAW blogger Joachim Bean suggests that the issues may be something related to PCI Express. Both the AirPort and graphics card are using PCI Express to communicate with the system.
that's nonsense, gfx and wlan has its own, dedicated pcie lines.
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raleedy said 5:37PM on 11-03-2009
So the airport cycle that is claimed to work, in fact doesn't?
Hendricus said 5:33PM on 11-03-2009
Hi everyone,
I have an iMac 2008 with 10.6.1 and even I experiance lagging with Flash. I dunno if this is the same experiance as the user of the new iMac 2009?
In Firefox Flash movies have trouble loading most of the times, or are very slow. With Safari is sluggish also.
Maybe it is my system, and this is not related to the lagging that the new iMac 2009 users notice?
If this is the same lag on different systems, then it is most probable that this "bug" is software related. I guess SL 10.6.1.
krg,
Hendricus
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Neil Cadsawan said 5:39PM on 11-03-2009
Try running Safari in 32bit mode instead of 64bit mode.
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Hugues said 5:53PM on 11-03-2009
You're right, this is not tied to the iMac but to Snow Leopard and 64bit Safari (with a 32bit flash plugin). We have the same issue with full page flash on a "just before last generation" 24" iMac
heathsnow said 5:52PM on 11-03-2009
I wasn't having the flash problem (21.5" iMac) but a Virtual Machine problem with the same 100% CPU issue. I posted my issue on the Apple forums last week and someone responded with this exact fix. It'll happen when the computer wakes from sleep as well.
In any case, cycling the wireless connection DOES fix it (thankfully). Now I don't have to use Boot Camp anymore (thankfully) but instead run VMware Fusion in Unity mode...w00t!
Heath
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David said 5:53PM on 11-03-2009
This is not a software issue -as the writer suggests. If you disable the airport altogether, the problem goes away. I've been running my 27" the last few days on the wired network, watching Flash content from Hulu for hours, with no slowdown. Before, I could use the machine for about an hour before it would grind to a halt.
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Robert said 6:25PM on 11-03-2009
I don't use wireless connectivity because my cable connection is on the wall directly behind my computer desk. As that's the case, am I to assume this slowdown issue should not be...well...an issue?
Matt said 8:00PM on 11-05-2009
Hi, I've been noticing this for a while on my late 2008 white macbook. Mostly on sites like ustream and other flash-intensive sites. So maybe the fix will work on mine too.
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Reed Moncsko said 6:25PM on 11-03-2009
Hey,
I work in a computer store, and we have definitely noticed this problem, even after reinstalling the operating system.
We are currently booting the computer into 64-bit kernel (hold 6 and 4 at boot), and the results have been amazing.
If anyone else can verify this, I would like to hear the results.
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Mathew Duggan said 6:28PM on 11-03-2009
I have not tried the 64 bit approach, but that isn't a good idea with Snow Leopard at this point. I don't know what it is about Flash, but Apple doesn't seem to be able to get it to work at a level anywhere near Linux or Windows.
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Jordan said 6:40PM on 11-03-2009
Interesting, all I've been seeing the last two days are Apple users bitching at Adobe for flash. Appears Adobe isn't the one at fault...Apple is.
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Charles said 6:42PM on 11-03-2009
I've been having problems as well (27"), and after reading countless threads on Apple's forums and others, there still seems to be no consensus about what the issue is, or even if it's only one issue. I was experiencing system-wide slow downs and crazy video artifacts and behavior like many. The first thing I did was check the permissions (every mac user's go-to) and they were all crazy and corrupted right out of the box. The next thing I tried was booting from the install disk, using the disk utility to completely erase and reformat the hard drive, and installed the OS fresh. It's been two days and my problems haven't returned. I'm not saying this is the fix, but it's worked for me so far (fingers crossed) and kept me from having to drag this beast down to the Apple Store.
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