malloc() in kernel and increasing mbuf and cluster size

From: kamal kc (kamal_ckk_at_yahoo.com)
Date: 10/17/05

  • Next message: kamal kc: "Re: malloc() in kernel and increasing mbuf and cluster size" 
    Date: Mon, 17 Oct 2005 04:49:01 -0700 (PDT)
To: freebsd-net@freebsd.org

    this may be a trivial question for many of you
    but i am confused in doing memory allocation in the
    kernel.

    sys/malloc.h has function prototypes for malloc()
    kern/kern_malloc.c defines the malloc()

    the malloc() definition is

    void *
    malloc(size, type, flags)
            unsigned long size;
            struct malloc_type *type;
            int flags;

    i understand the size and flags but what shall i
    do with the malloc_type.

    suppose i want to allocate 1024 bytes then how
    should i call the malloc ?

    i set -->
        size=1024
        flags=M_WAITOK
         type=???? (i don't know what/how to initialize
                  the type)

    Next thing is that i want to make the kernel process
    network packets very fast.
    i think of increasing the mbuf and cluster size.

    i want to if there will be any effect on increasing
    the mbuf and cluster size.

    what would be an appropriate size of mbuf and cluster
    if I use
     i. 512 MB RAM
     iI. 1024 MB RAM
     
    which parts of the kernel will be affected by
    changing the mbuf and cluster size ?

    i think somebody maybe able to help me.

    thanks folks.
    kamal

                    
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  • Next message: kamal kc: "Re: malloc() in kernel and increasing mbuf and cluster size"

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