[Don Pickett]

My G5 is showing a series of strange symptoms I can't track down, and I'm wondering if it could be RAM going bad, as bad RAM seems to produce weird symptoms. On my machine these include:

1) The machine will not sleep by itself;
2) Pausing iTunes while it's playing, and then starting it again, freezes the entire machine for several seconds;
3) Freezes and crashes in Safari 4 when viewing some pages with Flash in them;
4) A preference pane (EarthDesk) attempting to grab 3 GB of memory (the amount of RAM in my machine). I have contacted the makers of EarthDesk and they told me there's no code in the pref pane which would make it do such a thing.

With all of these problems together I'm beginning to think it's a hardware problem, and hoping it's one which is easily fixable. Could bad RAM contribute to symptoms like these?

In case anyone is interested, here is the memory error from EarthDesk:

Jul 4 14:25:55 Macintosh EarthDesk Core[4683]: EarthDesk Core(4683,0xf024b000) malloc: *** mmap(size=3388997632) failed (error code=12)\n*** error: can't allocate region\n*** set a breakpoint in malloc_error_break to debug
Jul 4 14:26:42 Macintosh GrowlHelperApp[154]: NetNewsWire: Feed Download Session Ended (New Items: 19\nUpdated Items: 1) - Priority 0
Jul 4 14:25:55 Macintosh [0x0-0xf50f5].com.xericdesign.earthdesk.core[4683]: EarthDesk Core(4683,0xf024b000) malloc: *** mmap(size=3388997632) failed (error code=12)
Jul 4 14:25:55 Macintosh [0x0-0xf50f5].com.xericdesign.earthdesk.core[4683]: *** error: can't allocate region
Jul 4 14:25:55 Macintosh [0x0-0xf50f5].com.xericdesign.earthdesk.core[4683]: *** set a breakpoint in malloc_error_break to debug

Forgot to mention: I have already done an Archive and Install to a fresh copy of 10.5.7, but that didn't help.

[CharlesS]

Originally Posted by Don Pickett 

4) A preference pane (EarthDesk) attempting to grab 3 GB of memory (the amount of RAM in my machine). I have contacted the makers of EarthDesk and they told me there's no code in the pref pane which would make it do such a thing.

Dunno if the other three might be caused by hardware or not (although No. 2 could be paging due to all the RAM being taken up), but this particular one is almost certainly EarthDesk's fault. Most likely they forgot to put an autorelease pool in a loop or something.

[Trygve]

I'm the developer of EarthDesk. We've seen no other reports of this and I can't imagine where it would try to alloc 3GB. We do use mmap, but only in one place and for a hard coded size of 131,292,913. The value you see is 3,388,997,632 which is a bit bigger than 25 times that size. This could be an endian issue in EarthDesk seeing as how you are on a PPC machine.

131,292,913 = 07 D3 5E F1
3,388,997,632 = CA 00 00 00

The last value is interesting in that it does not seem very random, but nothing in the code seems to mesh with it.
Do you have other machines to try this on?

The odd thing is that EarthDesk works even after reporting this - if it could not alloc the mmap space, it would not work at all.

[reader50]

A bad RAM stick might be a cause. A hard drive going bad could also cause symptoms like this. The pausing certainly. Open Disk Utility, select the hard drive, and check the SMART status at bottom of pane.

The requested amount of memory is 3 GB + 160 MB. Assuming your G5 has 3 GB RAM exactly, and EarthDesk requests 131,292,913 bytes (125+ MB) right as you run out of free RAM ... the vm system might request physical RAM size + 128 MB for EarthDesk + 32 MB for extra working space.

But I don't see why the log would show EarthDesk as having made the big request. It should show as a vm allocation (not a RAM request), credited to the kernel rather than the most recent app with a memory request. So this line of reasoning doesn't quite work.

Sometimes the simple answers are the ones to try. You already tried reinstalling the OS. How about installing a fresh copy of EarthDesk? Either from DVD or a fresh download - not sure how EarthDesk is distributed. A corrupted application could request an insane amount of RAM, which would cause all the other symptoms.

[CharlesS]

Originally Posted by Trygve 

I'm the developer of EarthDesk. We've seen no other reports of this and I can't imagine where it would try to alloc 3GB. We do use mmap, but only in one place and for a hard coded size of 131,292,913. The value you see is 3,388,997,632 which is a bit bigger than 25 times that size. This could be an endian issue in EarthDesk seeing as how you are on a PPC machine.

131,292,913 = 07 D3 5E F1
3,388,997,632 = CA 00 00 00

The last value is interesting in that it does not seem very random, but nothing in the code seems to mesh with it.
Do you have other machines to try this on?

The odd thing is that EarthDesk works even after reporting this - if it could not alloc the mmap space, it would not work at all.

It could be something else not related to the mmap - for example, if you have a loop that generates a lot of autoreleased objects but don't have an autorelease pool, that can do this quite quickly. Perhaps you should send him a build with some logs inserted to find out where exactly the memory-grabbing is occurring.

[Don Pickett]

The SMART status of both drives checks out in Disk Utility. If I get the free time I will try pulling some RAM and restarting.

[Back up 15 and punt]

One of the things that I recently have noticed about my sleep problem was that it was related to my kernel panics in that if I shut my machine down everyday I would suffer kernel panics multiple times per day. When I allow my machine to run without sleep , 24/7, it would remain stable. Of course, ever since 10.5.6 I have not been able to get my machine to sleep. But keep in mind that maintenance scripts are run early in the AM and If you run these scripts manually you will get around this kernel panic problem as well. I think Apple knows about this issue and is refusing to do anything about it!!!!!