[quagga-dev 1627] BGP Scalability Testing.

[RAMARAJAN, ARVIND, ALABS]

	Hi,
	 Does anyone on the list know any BGP Scalability [not functionality]
	testing against Quagga. Here we are trying BGP session (number of
	bgp peers) scalability test against Quagga (running on SUN Sparc 420R running
	Debian Sparc 2.4.27 kernel, 4GB mem and 2 UtltraSparc CPUs). The BGP sessions
	are generated using a Adtech Network tester/generator. We are hitting a dead
	wall once the number of sessions hits 1024, b'coz of select() FD_SETSIZE (max 1024)
	limit. Have tried different version of Quagga (from 0.96.5 to 0.97.1), no luck.
	Here is the snippet from the bgpd.log:

	2004/10/14 17:42:51 BGP: 10.74.0.9 [Event] Connect start to 10.74.0.9 fd 886
	2004/10/14 17:43:15 BGP: 10.20.15.205 [Event] Connect start to 10.20.15.205 fd 1023
	2004/10/14 17:43:15 BGP: 10.20.15.213 [Event] Connect start to 10.20.15.213 fd 1024
	2004/10/14 17:43:15 BGP: select() error: Bad file descriptor

	This apparently is spit from lib/thread.c

    733 thread_fetch (struct thread_master *m, struct thread *fetch)
    734 {
	<snip>
    780       num = select (FD_SETSIZE, &readfd, &writefd, &exceptfd, timer_wait);
    781
    782       if (num == 0)
    783         continue;
    784
    785       if (num < 0)
    786         {
    787           if (errno == EINTR)
    788             {
    789               /* signal received */
    790               quagga_sigevent_process ();
    791               continue;
    792             }
    793
    794           zlog_warn ("select() error: %s", strerror (errno));
    795             return NULL;
    796         }
    
	Once it hits the select 1024 limit, bgpd just dies silently , no core dump (ulimit -c
	unlimited; ulimit -n 2048)! Tried running from gdb does not produce any stacktrace!

	Lastly tried to bypass the hardlimit by using as compile time option CFLAGS=-DMAXFDS=2048
	also does not help. Has anyone done such testing or has reports of one. I know 1024 BGP
	sessions sounds big, we want to get to 2048!
						Thanx -->
							Arvind.

Arvind Ramarajan
Tier IV, Technology Insertion
AT&T
200 Laurel Av. S
Room: C2-2B38
Middletown NJ - 07748
Phone: (732)-420-2243
Fax: (732)-368-1601