Re: ls: can't open '.': Cannot allocate memory

Greg Ungerer <[email protected]>
Newsgroups gmane.linux.uclinux.devel
Message-ID <[email protected]>
Hi Luis,

On 30/10/12 05:38, Luis Alves wrote:
> Thanks for the explanation Larry.
>
> Meanwhile I've read some stuff about non-MMU memory alocation (I had
> the wrong idea of how memory was allocated).
> I guess my system ram is not that much (only 8Mb)...

What you are seeing though is a classic case of memory fragmentation.
You have eneough free RAM in total, but not enough in s ingle
contiguous block. On a paged MMU system this is not a problem, pages
can be mapped so you see a contiguous block the size you want. You
can't do that without no MMU and paging.


> How would shared libs solve the problem?
> The problem is allocating memory for 'ls' data and not 'ls' itself. Is
> this correct?

I would dig into the busybox ls code. Wanting to allocate a block of
512k in a single chunk seems a bit crazy.

Regards
Greg


> On Mon, Oct 29, 2012 at 5:49 PM, Larry Baker <[email protected]> wrote:
>> Luis,
>>
>> On 29 Oct 2012, at 8:32 AM, Luis Alves wrote:
>>
>> DMA: 36*4kB 30*8kB 29*16kB 21*32kB 6*64kB 7*128kB 4*256kB 3*512kB
>> 0*1024kB 0*2048kB 0*4096kB = 5360kB
>>
>>
>> The largest block of memory your system has available is 524288 (512*1024).
>>
>> Allocation of length 528384 from process 94 (ls) failed
>>
>>
>> The requested size is larger than that, so uClinux tries to allocate the
>> next larger block size (1024K).  There are none available.
>>
>> Any sugestion?
>>
>>
>> I do not know what determines how much memory ls allocates.
>>
>> I have similar memory allocation failures on my system.  It does not appear
>> to use a shared uclibc.  I do not know (yet) how to enable building a shared
>> uclibc or how to change the builds to use it.  If the instructions are
>> straightforward, I would like to hear from someone.
>>
>> Regards,
>> Luis
>> _______________________________________________
>> uClinux-dev mailing list
>> [email protected]
>> http://mailman.uclinux.org/mailman/listinfo/uclinux-dev
>> This message was resent by [email protected]
>> To unsubscribe see:
>> http://mailman.uclinux.org/mailman/options/uclinux-dev
>>
>>
>> Larry Baker
>> US Geological Survey
>> 650-329-5608
>> [email protected]
> _______________________________________________
> uClinux-dev mailing list
> [email protected]
> http://mailman.uclinux.org/mailman/listinfo/uclinux-dev
> This message was resent by [email protected]
> To unsubscribe see:
> http://mailman.uclinux.org/mailman/options/uclinux-dev
>
>
>


-- 
------------------------------------------------------------------------
Greg Ungerer  --  Principal Engineer        EMAIL:     [email protected]
SnapGear Group, McAfee                      PHONE:       +61 7 3435 2888
8 Gardner Close                             FAX:         +61 7 3217 5323
Milton, QLD, 4064, Australia                WEB: http://www.SnapGear.com
_______________________________________________
uClinux-dev mailing list
[email protected]
http://mailman.uclinux.org/mailman/listinfo/uclinux-dev
This message was resent by [email protected]
To unsubscribe see:
http://mailman.uclinux.org/mailman/options/uclinux-dev
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.