@@ -162,6 +162,17 @@ config IP_VS_FO
If you want to compile it in kernel, say Y. To compile it as a
module, choose M here. If unsure, say N.
+config IP_VS_OVF
+ tristate "weighted overflow scheduling"
+ ---help---
+ The weighted overflow scheduling algorithm directs network
+ connections to the server with the highest weight that is
+ currently available and overflows to the next when active
+ connections exceed the node's weight.
+
+ If you want to compile it in kernel, say Y. To compile it as a
+ module, choose M here. If unsure, say N.
+
config IP_VS_LBLC
tristate "locality-based least-connection scheduling"
---help---
@@ -27,6 +27,7 @@ obj-$(CONFIG_IP_VS_WRR) += ip_vs_wrr.o
obj-$(CONFIG_IP_VS_LC) += ip_vs_lc.o
obj-$(CONFIG_IP_VS_WLC) += ip_vs_wlc.o
obj-$(CONFIG_IP_VS_FO) += ip_vs_fo.o
+obj-$(CONFIG_IP_VS_OVF) += ip_vs_ovf.o
obj-$(CONFIG_IP_VS_LBLC) += ip_vs_lblc.o
obj-$(CONFIG_IP_VS_LBLCR) += ip_vs_lblcr.o
obj-$(CONFIG_IP_VS_DH) += ip_vs_dh.o
new file mode 100644
@@ -0,0 +1,86 @@
+/*
+ * IPVS: Overflow-Connection Scheduling module
+ *
+ * Authors: Raducu Deaconu <rhadoo_io@yahoo.com>
+ *
+ * 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.
+ *
+ * Scheduler implements "overflow" loadbalancing according to number of active
+ * connections , will keep all conections to the node with the highest weight
+ * and overflow to the next node if the number of connections exceeds the node's
+ * weight.
+ * Note that this scheduler might not be suitable for UDP because it only uses
+ * active connections
+ *
+ */
+
+#define KMSG_COMPONENT "IPVS"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+
+#include <net/ip_vs.h>
+
+/* OVF Connection scheduling */
+static struct ip_vs_dest *
+ip_vs_ovf_schedule(struct ip_vs_service *svc, const struct sk_buff *skb,
+ struct ip_vs_iphdr *iph)
+{
+ struct ip_vs_dest *dest, *h = NULL;
+ int hw = 0, w;
+
+ IP_VS_DBG(6, "ip_vs_ovf_schedule(): Scheduling...\n");
+ /* select the node with highest weight, go to next in line if active
+ * connections exceed weight
+ */
+ list_for_each_entry_rcu(dest, &svc->destinations, n_list) {
+ w = atomic_read(&dest->weight);
+ if ((dest->flags & IP_VS_DEST_F_OVERLOAD) ||
+ atomic_read(&dest->activeconns) > w ||
+ w == 0)
+ continue;
+ if (!h || w > hw) {
+ h = dest;
+ hw = w;
+ }
+ }
+
+ if (h) {
+ IP_VS_DBG_BUF(6, "OVF: server %s:%u active %d w %d\n",
+ IP_VS_DBG_ADDR(h->af, &h->addr),
+ ntohs(h->port),
+ atomic_read(&h->activeconns),
+ atomic_read(&h->weight));
+ return h;
+ }
+
+ ip_vs_scheduler_err(svc, "no destination available");
+ return NULL;
+}
+
+static struct ip_vs_scheduler ip_vs_ovf_scheduler = {
+ .name = "ovf",
+ .refcnt = ATOMIC_INIT(0),
+ .module = THIS_MODULE,
+ .n_list = LIST_HEAD_INIT(ip_vs_ovf_scheduler.n_list),
+ .schedule = ip_vs_ovf_schedule,
+};
+
+static int __init ip_vs_ovf_init(void)
+{
+ return register_ip_vs_scheduler(&ip_vs_ovf_scheduler);
+}
+
+static void __exit ip_vs_ovf_cleanup(void)
+{
+ unregister_ip_vs_scheduler(&ip_vs_ovf_scheduler);
+ synchronize_rcu();
+}
+
+module_init(ip_vs_ovf_init);
+module_exit(ip_vs_ovf_cleanup);
+MODULE_LICENSE("GPL");