Re: [ECOS] eCos + goAhead probelm

[Hao <hao at hao dot dns2go dot com>]

I only change one line in the function balloc() in balloc.c

goAhead version: 218
orignal file (line 259 ~ 263)==>
           bp = (bType*) malloc(memSize);
           if (bp == NULL) {
               traceRaw(T("B: malloc failed\n"));
               return NULL;
           }

modified ==>
           bp = (bType*) malloc(memSize + 64);
           if (bp == NULL) {
               traceRaw(T("B: malloc failed\n"));
               return NULL;
           }

goAhead pre-allocate a lot of memory(about 60KB) at bopen() to build 
it's own memory pool.
When it need some memory, it will get it from it's own memory pool 
first, if the memory pool is empty,
then it call malloc() to get memory from eCos.
So, the balloc()  will check it's own memory pool first. if empty, then 
call malloc().
Because you increase the pool size of goAhead. So the balloc() never 
call malloc() to get new memory.

I try to put lots of debug message to trace the bug. Then I found eCos 
's memory pool information is overwirtten by goAhead.
So, I think the problem is goAhead use balloc() to get some memory, and 
the pre-allocate memory pool is already empty.
Then it call malloc() to get new memory from eCos.
After this, goAhead put too much data(more than the size it allocated) 
to this buffer, cause eCos 's memory pool information crashed.

Now, I don't have time to found real murderer in goAhead.
But hope it can give you a direction to solve your problem.

Hao


> After some more tests, I've got a stable web server when I call bopen()
> with a bufsize of 1.25M !
> (1M is still not enough - I could bring it to crash after a massive set
> of requests... )
> Does it make sense?
>
> What is the malloc size you're using for balloc's malloc() to solve the
> out of memory problem?
>
> Thanks,
> -- Amir
>
> -----Original Message-----
> From: ecos-discuss-owner@ecos.sourceware.org
> [mailto:ecos-discuss-owner@ecos.sourceware.org]On Behalf Of Hao
> Sent: Tuesday, August 17, 2004 6:41 AM
> To: ecos-discuss@sources.redhat.com
> Subject: Re: [ECOS] eCos + goAhead probelm
>
>
>
> Recently,  I modify balloc() in balloc.c of goAhead.
> I try to increase 64bytes at the line of  malloc() .  And the problem of 
> out of memory disappeared.
> So , I think it's not the probelm caused by eCos.
> I think it's caused by goAhead somewhere that call balloc() and use 
> wrong size.
>
> Now, in my target, goAhead still unstable just like you say. Then I use 
> very simple web page instead of default web page(home.asp).
> It still unstable, but not crashed.
> But it can work very fine when I use 'lynx' instead of other browser(IE, 
> mozilla..).
> I don't know what's the difference of behavior between lynx and other 
> browser (IE,mozilla).
>
> Hope this information can help you something.
>
> Hao
>
>
>  


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