diff options
Diffstat (limited to 'net/ipv4/ipvs/ip_vs_nq.c')
-rw-r--r-- | net/ipv4/ipvs/ip_vs_nq.c | 138 |
1 files changed, 0 insertions, 138 deletions
diff --git a/net/ipv4/ipvs/ip_vs_nq.c b/net/ipv4/ipvs/ip_vs_nq.c deleted file mode 100644 index 9a2d8033f08..00000000000 --- a/net/ipv4/ipvs/ip_vs_nq.c +++ /dev/null @@ -1,138 +0,0 @@ -/* - * IPVS: Never Queue scheduling module - * - * Authors: Wensong Zhang <wensong@linuxvirtualserver.org> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version - * 2 of the License, or (at your option) any later version. - * - * Changes: - * - */ - -/* - * The NQ algorithm adopts a two-speed model. When there is an idle server - * available, the job will be sent to the idle server, instead of waiting - * for a fast one. When there is no idle server available, the job will be - * sent to the server that minimize its expected delay (The Shortest - * Expected Delay scheduling algorithm). - * - * See the following paper for more information: - * A. Weinrib and S. Shenker, Greed is not enough: Adaptive load sharing - * in large heterogeneous systems. In Proceedings IEEE INFOCOM'88, - * pages 986-994, 1988. - * - * Thanks must go to Marko Buuri <marko@buuri.name> for talking NQ to me. - * - * The difference between NQ and SED is that NQ can improve overall - * system utilization. - * - */ - -#include <linux/module.h> -#include <linux/kernel.h> - -#include <net/ip_vs.h> - - -static inline unsigned int -ip_vs_nq_dest_overhead(struct ip_vs_dest *dest) -{ - /* - * We only use the active connection number in the cost - * calculation here. - */ - return atomic_read(&dest->activeconns) + 1; -} - - -/* - * Weighted Least Connection scheduling - */ -static struct ip_vs_dest * -ip_vs_nq_schedule(struct ip_vs_service *svc, const struct sk_buff *skb) -{ - struct ip_vs_dest *dest, *least = NULL; - unsigned int loh = 0, doh; - - IP_VS_DBG(6, "ip_vs_nq_schedule(): Scheduling...\n"); - - /* - * We calculate the load of each dest server as follows: - * (server expected overhead) / dest->weight - * - * Remember -- no floats in kernel mode!!! - * The comparison of h1*w2 > h2*w1 is equivalent to that of - * h1/w1 > h2/w2 - * if every weight is larger than zero. - * - * The server with weight=0 is quiesced and will not receive any - * new connections. - */ - - list_for_each_entry(dest, &svc->destinations, n_list) { - - if (dest->flags & IP_VS_DEST_F_OVERLOAD || - !atomic_read(&dest->weight)) - continue; - - doh = ip_vs_nq_dest_overhead(dest); - - /* return the server directly if it is idle */ - if (atomic_read(&dest->activeconns) == 0) { - least = dest; - loh = doh; - goto out; - } - - if (!least || - (loh * atomic_read(&dest->weight) > - doh * atomic_read(&least->weight))) { - least = dest; - loh = doh; - } - } - - if (!least) - return NULL; - - out: - IP_VS_DBG_BUF(6, "NQ: server %s:%u " - "activeconns %d refcnt %d weight %d overhead %d\n", - IP_VS_DBG_ADDR(svc->af, &least->addr), ntohs(least->port), - atomic_read(&least->activeconns), - atomic_read(&least->refcnt), - atomic_read(&least->weight), loh); - - return least; -} - - -static struct ip_vs_scheduler ip_vs_nq_scheduler = -{ - .name = "nq", - .refcnt = ATOMIC_INIT(0), - .module = THIS_MODULE, - .n_list = LIST_HEAD_INIT(ip_vs_nq_scheduler.n_list), -#ifdef CONFIG_IP_VS_IPV6 - .supports_ipv6 = 1, -#endif - .schedule = ip_vs_nq_schedule, -}; - - -static int __init ip_vs_nq_init(void) -{ - return register_ip_vs_scheduler(&ip_vs_nq_scheduler); -} - -static void __exit ip_vs_nq_cleanup(void) -{ - unregister_ip_vs_scheduler(&ip_vs_nq_scheduler); -} - -module_init(ip_vs_nq_init); -module_exit(ip_vs_nq_cleanup); -MODULE_LICENSE("GPL"); |