diff options
Diffstat (limited to 'net/ipv4/ipvs/ip_vs_sed.c')
| -rw-r--r-- | net/ipv4/ipvs/ip_vs_sed.c | 161 |
1 files changed, 0 insertions, 161 deletions
diff --git a/net/ipv4/ipvs/ip_vs_sed.c b/net/ipv4/ipvs/ip_vs_sed.c deleted file mode 100644 index 77663d84cbd1..000000000000 --- a/net/ipv4/ipvs/ip_vs_sed.c +++ /dev/null @@ -1,161 +0,0 @@ -/* - * IPVS: Shortest Expected Delay 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 SED algorithm attempts to minimize each job's expected delay until - * completion. The expected delay that the job will experience is - * (Ci + 1) / Ui if sent to the ith server, in which Ci is the number of - * jobs on the ith server and Ui is the fixed service rate (weight) of - * the ith server. The SED algorithm adopts a greedy policy that each does - * what is in its own best interest, i.e. to join the queue which would - * minimize its expected delay of completion. - * - * 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 SED to me. - * - * The difference between SED and WLC is that SED includes the incoming - * job in the cost function (the increment of 1). SED may outperform - * WLC, while scheduling big jobs under larger heterogeneous systems - * (the server weight varies a lot). - * - */ - -#include <linux/module.h> -#include <linux/kernel.h> - -#include <net/ip_vs.h> - - -static int -ip_vs_sed_init_svc(struct ip_vs_service *svc) -{ - return 0; -} - - -static int -ip_vs_sed_done_svc(struct ip_vs_service *svc) -{ - return 0; -} - - -static int -ip_vs_sed_update_svc(struct ip_vs_service *svc) -{ - return 0; -} - - -static inline unsigned int -ip_vs_sed_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_sed_schedule(struct ip_vs_service *svc, const struct sk_buff *skb) -{ - struct ip_vs_dest *dest, *least; - unsigned int loh, doh; - - IP_VS_DBG(6, "ip_vs_sed_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) > 0) { - least = dest; - loh = ip_vs_sed_dest_overhead(least); - goto nextstage; - } - } - return NULL; - - /* - * Find the destination with the least load. - */ - nextstage: - list_for_each_entry_continue(dest, &svc->destinations, n_list) { - if (dest->flags & IP_VS_DEST_F_OVERLOAD) - continue; - doh = ip_vs_sed_dest_overhead(dest); - if (loh * atomic_read(&dest->weight) > - doh * atomic_read(&least->weight)) { - least = dest; - loh = doh; - } - } - - IP_VS_DBG(6, "SED: server %u.%u.%u.%u:%u " - "activeconns %d refcnt %d weight %d overhead %d\n", - NIPQUAD(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_sed_scheduler = -{ - .name = "sed", - .refcnt = ATOMIC_INIT(0), - .module = THIS_MODULE, - .n_list = LIST_HEAD_INIT(ip_vs_sed_scheduler.n_list), - .init_service = ip_vs_sed_init_svc, - .done_service = ip_vs_sed_done_svc, - .update_service = ip_vs_sed_update_svc, - .schedule = ip_vs_sed_schedule, -}; - - -static int __init ip_vs_sed_init(void) -{ - return register_ip_vs_scheduler(&ip_vs_sed_scheduler); -} - -static void __exit ip_vs_sed_cleanup(void) -{ - unregister_ip_vs_scheduler(&ip_vs_sed_scheduler); -} - -module_init(ip_vs_sed_init); -module_exit(ip_vs_sed_cleanup); -MODULE_LICENSE("GPL"); |