Attempt to make the host route cache a bit smarter under conditions of

high load:

	1) If there ever get to be more than net.inet.ip.rtmaxcache entries
	   in the cache, in_rtqtimo() will reduce net.inet.ip.rtexpire by
	   1/3 and do another round, unles net.inet.ip.rtexpire is less than
	   net.inet.ip.rtminexpire, and never more than once in ten minutes
	   (rtq_timeout).

	2) If net.inet.ip.rtexpire is set to zero, don't bother to cache
	   anything.
This commit is contained in:
Garrett Wollman 1995-02-14 23:04:52 +00:00
parent 1bc2211b44
commit ea80aed1a9
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=6399
3 changed files with 90 additions and 14 deletions

View File

@ -31,7 +31,7 @@
* SUCH DAMAGE.
*
* @(#)in.h 8.3 (Berkeley) 1/3/94
* $Id: in.h,v 1.5 1994/12/14 19:06:36 wollman Exp $
* $Id: in.h,v 1.6 1994/12/21 17:23:59 wollman Exp $
*/
#ifndef _NETINET_IN_H_
@ -227,7 +227,9 @@ struct ip_mreq {
#define IPCTL_DEFMTU 4 /* default MTU */
#endif
#define IPCTL_RTEXPIRE 5 /* cloned route expiration time */
#define IPCTL_MAXID 6
#define IPCTL_RTMINEXPIRE 6 /* min value for expiration time */
#define IPCTL_RTMAXCACHE 7 /* trigger level for dynamic expire */
#define IPCTL_MAXID 8
#define IPCTL_NAMES { \
{ 0, 0 }, \
@ -236,6 +238,8 @@ struct ip_mreq {
{ "ttl", CTLTYPE_INT }, \
{ "mtu", CTLTYPE_INT }, \
{ "rtexpire", CTLTYPE_INT }, \
{ "rtminexpire", CTLTYPE_INT }, \
{ "rtmaxcache", CTLTYPE_INT }, \
}

View File

@ -1,10 +1,32 @@
/*
* Copyright 1994, Massachusetts Institute of Technology. All Rights Reserved.
* Copyright 1994, 1995 Massachusetts Institute of Technology
*
* You may copy this file verbatim until I find the official
* Institute boilerplate.
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby
* granted, provided that both the above copyright notice and this
* permission notice appear in all copies, that both the above
* copyright notice and this permission notice appear in all
* supporting documentation, and that the name of M.I.T. not be used
* in advertising or publicity pertaining to distribution of the
* software without specific, written prior permission. M.I.T. makes
* no representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied
* warranty.
*
* THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
* ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
* SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $Id: in_rmx.c,v 1.7 1994/12/21 17:25:52 wollman Exp $
* $Id: in_rmx.c,v 1.8 1995/01/23 02:02:50 wollman Exp $
*/
/*
@ -79,8 +101,9 @@ in_matroute(void *v_arg, struct radix_node_head *head)
return rn;
}
#define RTQ_REALLYOLD 60*60 /* one hour is ``really old'' */
int rtq_reallyold = RTQ_REALLYOLD;
int rtq_reallyold = 60*60; /* one hour is ``really old'' */
int rtq_toomany = 128; /* 128 cached routes is ``too many'' */
int rtq_minreallyold = 10; /* never automatically crank down to less */
/*
* On last reference drop, mark the route as belong to us so that it can be
@ -101,8 +124,20 @@ in_clsroute(struct radix_node *rn, struct radix_node_head *head)
!= RTF_WASCLONED)
return;
rt->rt_flags |= RTPRF_OURS;
rt->rt_rmx.rmx_expire = time.tv_sec + rtq_reallyold;
/*
* As requested by David Greenman:
* If rtq_reallyold is 0, just delete the route without
* waiting for a timeout cycle to kill it.
*/
if(rtq_reallyold != 0) {
rt->rt_flags |= RTPRF_OURS;
rt->rt_rmx.rmx_expire = time.tv_sec + rtq_reallyold;
} else {
rtrequest(RTM_DELETE,
(struct sockaddr *)rt_key(rt),
rt->rt_gateway, rt_mask(rt),
rt->rt_flags, 0);
}
}
struct rtqk_arg {
@ -128,7 +163,8 @@ in_rtqkill(struct radix_node *rn, void *rock)
if(rt->rt_flags & RTPRF_OURS) {
ap->found++;
if(ap->draining || rt->rt_rmx.rmx_expire <= time.tv_sec) {
if(ap->draining || rt->rt_rmx.rmx_expire <= time.tv_sec
|| (rt->rt_rmx.rmx_expire - time.tv_sec > rtq_reallyold)) {
if(rt->rt_refcnt > 0)
panic("rtqkill route really not free\n");
@ -150,7 +186,7 @@ in_rtqkill(struct radix_node *rn, void *rock)
return 0;
}
#define RTQ_TIMEOUT 600 /* run no less than once every ten minutes */
#define RTQ_TIMEOUT 60*10 /* run no less than once every ten minutes */
int rtq_timeout = RTQ_TIMEOUT;
static void
@ -159,6 +195,7 @@ in_rtqtimo(void *rock)
struct radix_node_head *rnh = rock;
struct rtqk_arg arg;
struct timeval atv;
static time_t last_adjusted_timeout = 0;
int s;
arg.found = arg.killed = 0;
@ -168,6 +205,32 @@ in_rtqtimo(void *rock)
s = splnet();
rnh->rnh_walktree(rnh, in_rtqkill, &arg);
splx(s);
/*
* Attempt to be somewhat dynamic about this:
* If there are ``too many'' routes sitting around taking up space,
* then crank down the timeout, and see if we can't make some more
* go away. However, we make sure that we will never adjust more
* than once in rtq_timeout seconds, to keep from cranking down too
* hard.
*/
if((arg.found - arg.killed > rtq_toomany)
&& (time.tv_sec - last_adjusted_timeout >= rtq_timeout)
&& rtq_reallyold > rtq_minreallyold) {
rtq_reallyold = 2*rtq_reallyold / 3;
if(rtq_reallyold < rtq_minreallyold) {
rtq_reallyold = rtq_minreallyold;
}
last_adjusted_timeout = time.tv_sec;
log(LOG_DEBUG, "in_rtqtimo: adjusted rtq_reallyold to %d",
rtq_reallyold);
arg.found = arg.killed = 0;
s = splnet();
rnh->rnh_walktree(rnh, in_rtqkill, &arg);
splx(s);
}
atv.tv_usec = 0;
atv.tv_sec = arg.nextstop;
timeout(in_rtqtimo, rock, hzto(&atv));

View File

@ -31,7 +31,7 @@
* SUCH DAMAGE.
*
* @(#)ip_input.c 8.2 (Berkeley) 1/4/94
* $Id: ip_input.c,v 1.15 1995/01/12 13:06:30 ugen Exp $
* $Id: ip_input.c,v 1.16 1995/02/07 20:30:42 gpalmer Exp $
*/
#include <sys/param.h>
@ -1188,6 +1188,8 @@ ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
size_t newlen;
{
extern int rtq_reallyold; /* XXX */
extern int rtq_minreallyold; /* XXX */
extern int rtq_toomany; /* XXX */
/* All sysctl names at this level are terminal. */
if (namelen != 1)
@ -1206,7 +1208,14 @@ ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu));
#endif
case IPCTL_RTEXPIRE:
return (sysctl_int(oldp, oldlenp, newp, newlen, &rtq_reallyold));
return (sysctl_int(oldp, oldlenp, newp, newlen,
&rtq_reallyold));
case IPCTL_RTMINEXPIRE:
return (sysctl_int(oldp, oldlenp, newp, newlen,
&rtq_minreallyold));
case IPCTL_RTMAXCACHE:
return (sysctl_int(oldp, oldlenp, newp, newlen,
&rtq_toomany));
default:
return (EOPNOTSUPP);
}