[mpls-linux-general] MPLS Performance Improvement

[Sasa P. <sas...@fe...>]

To improve MPLS performance do this:

1. in /usr/src/linux/include/net/mpls.h file comment following lines:

/* Comment this to suppress MPLS_DEBUG calls */
//#define MPLS_ENABLE_DEBUG 1

/* Comment this to suppress TRACING enter/exit functions */
//#define MPLS_ENABLE_DEBUG_FUNC 1


2. in /usr/src/linux/net/mpls/mpls_utils.c do this:

void
mpls_skb_dump (struct sk_buff* sk)
{
        return;

/* THIS IS IRRELEVANT
        unsigned int i;
        if (!mpls_debug)
                return;

        printk("MPLS mpls_skb_dump: from %s with len %d (%d)"
               "headroom=%d tailroom=%d\n",
                        sk->dev?sk->dev->name:" net stack ",
                        sk->len,
                        sk->truesize,
                        skb_headroom(sk),
                        skb_tailroom(sk));

        for (i=(unsigned int)sk->head; i<=(unsigned int)sk->tail; i++) {
                if (i == (unsigned int)sk->data)
                        printk("{");
                if (i == (unsigned int)sk->h.raw)
                        printk("#");
                if (i == (unsigned int)sk->nh.raw)
                        printk("|");
                if (i == (unsigned int)sk->mac.raw)
                        printk("*");
                printk("%02x",*((unsigned char*)i));
                if (i == (unsigned int)sk->tail)
                        printk("}");
        }
        printk("\n");
*/
}

With this, I improve throughput 40 times. (over 6 MPLS nodes with 
netperf; Source and Destination are IP nodes)

THROUGHPUT BEFORE: 0.35 Mbps

THROUGHPUT AFTER: 13.01 Mbps !!!!