question on system() and fork() on Linux w/no overcommit

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question on system() and fork() on Linux w/no overcommit

Van Horne, John
We have an embedded system using:
    glibc 2.4
    Linux kernel 2.6.14

Because it is an embedded system with limited virtual memory and where
we can't allow
processes to die due to a failed allocation, we have the kernel
configured with memory
overcommit disabled.

We have one process which takes up more than half of the available
virtual memory. If
from this process we call system(), it fails because the underlying
fork() cannot get
enough virtual memory to make a virtual copy. Our Linux kernel guy is
suggesting that
we patch glibc's system() so that it uses vfork() instead of fork().

Has anyone else working on systems with memory overcommit disabled
encountered this
problem, and how did you resolve it? Is this the right approach, or is
there a better


     - - - - - Appended by Scientific Atlanta, a Cisco company - - - - -
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