Swap file limitations of OSX?

[Fahrvergnuugen]

Is there a limitation to the amount of memory [both virtual and physical] that an application can use?

I'm getting this error when trying to run a php script that i wrote [yes, its supposed to use a ton of ram, its doing something rather amazing...]

*** malloc: vm_allocate(size=262144) failed with 3
*** malloc[1146]: error: Can't allocate region
FATAL: emalloc(): Unable to allocate 260000 bytes

 

[seann]

I highly doubt its doing something amazing if it takes that much memory.

Enlighten us.

 

[Fahrvergnuugen]

its assembling over a million photographs into one giant image which will be 65,000 pixels wide by 65,000 pixels tall [limited by the capabilities of GD].

 

[Arden]

And you can't up the RAM to 1.5 GB?

AFAIK, OS X uses invisible files to use as Virtual Memory. I don't know how big these files are, but they are limited (naturally) by the size of your hard drive. Do you have a lot of HD space left?

What's GD, BTW?

 

[seann]

ahh..amazingly large.

I'm gonna do some horrible math here.
65,000x65,000 =
bytes: 12675000000
kilobytes: 12377929.6875
megs: 12087.82196044921875

results computed from:
http://www.imaging-resource.com/ARTS/NEWYEAR/NEWYEAR.HTM
11 gig swap file?

 

[Fahrvergnuugen]

I'm already maxed out on physical ram. 1.2GB isn't nearly enough RAM to allocate a truetype image thats 65,000 * 65,000 pixels.

as soon as PHP has consumed 4GB of virtual memory, it errors out. I watched its progress in top:

1164 php 85.6% 1:21.70 1 12 21673 1.12G+ 64K 144M- 3.99G+

 

[Fahrvergnuugen]

and yes I have more than 4GB free on my system drive.

 

[naodx]

One thing that you could try, is typing: ls -Fal /private/var/vm in a terminal window and see how many swapfile(s) the os has made. If there are quite a few, then yes you are hitting the vm pretty hard.

Another possibility is that you are encountering the infamous malloc bug that has been part of os x since its days as next step.

I encountered this bug while doing a program in c for a class I was taking. One of my instructors friends still does some developement for open/next step, and he said that there has been a problem with malloc for years.

Infact he also said that many next programmers ended up writing there own version of malloc to bypass this bug.

Doing a search on google verified this malloc bug does/did exist.

Again, this might not have anything to do with the problem that you are encountering.

I'd check the /private/var/vm directory first for the number of swap files, if that isn't it then maybe the other info I gave you could help.

Good luck

 

[Arden]

Seann: why stress yourself? Let Google do the math.

 

[Fahrvergnuugen]

naodx, thanks for the info on malloc, I'll see what I can find.

Heres what my vm directory looks like

[darklotus:~] reloaded% ls -Fal /private/var/vm/
total 3281376
drwxr-xr-x 45 root wheel 1530 Aug 26 22:38 ./
drwxr-xr-x 22 root wheel 748 Aug 25 17:57 ../
drwx--x--x 12 root wheel 408 Aug 25 17:48 app_profile/
-rw------T 1 root wheel 80000000 Aug 25 17:57 swapfile0
-rw------T 1 root wheel 80000000 Aug 25 21:47 swapfile1
-rw------T 1 root wheel 80000000 Aug 26 11:02 swapfile10
-rw------T 1 root wheel 80000000 Aug 26 11:02 swapfile11
-rw------T 1 root wheel 80000000 Aug 26 20:23 swapfile12
-rw------T 1 root wheel 80000000 Aug 26 20:23 swapfile13
-rw------T 1 root wheel 80000000 Aug 26 20:23 swapfile14
-rw------T 1 root wheel 80000000 Aug 26 20:23 swapfile15
-rw------T 1 root wheel 80000000 Aug 26 20:24 swapfile16
-rw------T 1 root wheel 80000000 Aug 26 20:24 swapfile17
-rw------T 1 root wheel 80000000 Aug 26 20:24 swapfile18
-rw------T 1 root wheel 80000000 Aug 26 22:32 swapfile19
-rw------T 1 root wheel 80000000 Aug 25 21:47 swapfile2
-rw------T 1 root wheel 80000000 Aug 26 22:32 swapfile20
-rw------T 1 root wheel 80000000 Aug 26 22:32 swapfile21
-rw------T 1 root wheel 80000000 Aug 26 22:32 swapfile22
-rw------T 1 root wheel 80000000 Aug 26 22:32 swapfile23
-rw------T 1 root wheel 80000000 Aug 26 22:33 swapfile24
-rw------T 1 root wheel 80000000 Aug 26 22:33 swapfile25
-rw------T 1 root wheel 80000000 Aug 26 22:33 swapfile26
-rw------T 1 root wheel 80000000 Aug 26 22:33 swapfile27
-rw------T 1 root wheel 80000000 Aug 26 22:33 swapfile28
-rw------T 1 root wheel 80000000 Aug 26 22:33 swapfile29
-rw------T 1 root wheel 80000000 Aug 25 21:48 swapfile3
-rw------T 1 root wheel 80000000 Aug 26 22:33 swapfile30
-rw------T 1 root wheel 80000000 Aug 26 22:34 swapfile31
-rw------T 1 root wheel 80000000 Aug 26 22:34 swapfile32
-rw------T 1 root wheel 80000000 Aug 26 22:35 swapfile33
-rw------T 1 root wheel 80000000 Aug 26 22:35 swapfile34
-rw------T 1 root wheel 80000000 Aug 26 22:35 swapfile35
-rw------T 1 root wheel 80000000 Aug 26 22:36 swapfile36
-rw------T 1 root wheel 80000000 Aug 26 22:36 swapfile37
-rw------T 1 root wheel 80000000 Aug 26 22:37 swapfile38
-rw------T 1 root wheel 80000000 Aug 26 22:37 swapfile39
-rw------T 1 root wheel 80000000 Aug 26 11:01 swapfile4
-rw------T 1 root wheel 80000000 Aug 26 22:38 swapfile40
-rw------T 1 root wheel 80000000 Aug 26 22:38 swapfile41
-rw------T 1 root wheel 80000000 Aug 26 11:01 swapfile5
-rw------T 1 root wheel 80000000 Aug 26 11:01 swapfile6
-rw------T 1 root wheel 80000000 Aug 26 11:01 swapfile7
-rw------T 1 root wheel 80000000 Aug 26 11:01 swapfile8
-rw------T 1 root wheel 80000000 Aug 26 11:02 swapfile9

 

[naodx]

Ya, I'd say you were hitting the hard drive pretty good....and I'm not sure where you would find any information on size limitations for vm.

Maybe on apple's developer site?