Answer / feroz ahmed

The problem is because of memory fragmentation..

Though 10KB of memory is available but it will be in
smaller chunks (less than 5KB).. when we request for 5KB
malloc returns NULL as it coudnt find a chunk of size 5KB...

Answer / laxman.vallandas

It may be becoz of two things.
1.External Fragmentation.
2.Memory leak
Due to external fragmentation 5 kb of memory will not be
allocated even though 10 kb of memory is available because
the memory is in chunks of size less than 5 kb.so wen u try
to allocate memory since malloc returns chunks of contigous
memory ,it returns NULL.
Reason 2:
If memory is allocated dynamically may be in other files or
process and which was not been deallocated yet which
results in memory leaks .

Answer / ravidevroy

This might be because, you might be allocating memory
dynamically from the heap. But care is not taken to
deallocate the same.
as a result, there are memory leaks and finally the os says
that there is no free memory

Answer / mohan

RTOS might be having 10k memory, might not fragmentation
problem, and the largest hole available to user might be
lesser than 5k, this condition might be one of the reason
for NULL error.

What is priority inversion?

10 Answers   Juniper Networks,

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IN RTOS HAVING 1OKBYTES OF MEMORY AND YOUR PROGRAMM FOR ASKING FOR 5KBYTES AND YOU GOT NULL ERROR ? WHY DOES IT BEHAVES LIKE THIS

4 Answers  

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what is task spawn in vxworks ?plz anyone explain me

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what are the various methods to overcome it?

2 Answers   Vector India,

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What is another for creating a task without using taskspawn?

2 Answers  

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Assume there is a global variable & a static global variable.Both gets memory allocated from the data segment. Then how does the visiblity of static global varible gets limited to the file alone (in which it gets declared) ???

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4 Answers  

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what do u mean by Semaphore..when v wil go for using this..explain about hat.what is the difference betw..binary ,,counting and mutex semphores

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Which RTOS supports Non-Preemptive scheduling ? Why other scheduling methods are supported by such Oses?

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Write a code to connect Hardware interrupt to ISR...?

1 Answers   iNet, Wipro,

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hi this is srikanth i need video classes for Vxworks any body having this forward me thanking u

1 Answers   DELL, Wipro,

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