Hi,
I have updated the code and generated the patch, according to your indications.
On Tue, Jul 14, 2015 at 10:11 PM, Julian Anastasov <ja@xxxxxx> wrote:
>
> Hello,
>
> On Tue, 14 Jul 2015, rhadoo.io88 wrote:
>
>> Unfortunately i was not aware of the FO scheduler, i looked it up just
>> now...indeed you could get similar behavior with FO scheduler and
>> proper thresholds.
>> The only trouble with that is that i can't set the thresholds from
>> within ldirectord , so i won't be able to keep all the config in one
>> place, and that upper threshold seems to take into account all
>> connections ( active and inactive) , that making the upper limit a bit
>> vague.
>> i think this approach has the advantage of keeping all the config in
>> one place, having the weight set at the actual number of active
>> connections the node can handle whilst still allowing to have
>> thresholds on the total connections.
>
> OK. But you have to update this scheduler because
> it is based on old code. You can use ip_vs_fo.c for
> reference. You have to fix any coding style warnings by using
> scripts/checkpatch.pl --strict /tmp/your.patch
> You can check Documentation/CodingStyle for reference.
> You can add comment that this scheduler can be used
> for TCP/SCTP but not for UDP because it uses only the
> activeconns.
>
> Your patch should include also changes for Kconfig
> and Makefile.
>
> Also, the 'curentw = atomic_read(&dest->weight);'
> can be used early to read the weight only once.
>
> Regards
>
> --
> Julian Anastasov <ja@xxxxxx>
From 69eab2c6e5add4e565b882fd91959de9cb8526fb Mon Sep 17 00:00:00 2001
From: Raducu Deaconu <rhadoo.io88@xxxxxxxxx>
Date: Thu, 16 Jul 2015 08:54:16 +0300
Subject: [PATCH] Add ovf scheduler
Signed-off-by: Raducu Deaconu <rhadoo.io88@xxxxxxxxx>
---
net/netfilter/ipvs/Kconfig | 11 +++++
net/netfilter/ipvs/Makefile | 1 +
net/netfilter/ipvs/ip_vs_ovf.c | 87 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 99 insertions(+)
create mode 100644 net/netfilter/ipvs/ip_vs_ovf.c
diff --git a/net/netfilter/ipvs/Kconfig b/net/netfilter/ipvs/Kconfig
index 3b6929d..2563c18 100644
--- a/net/netfilter/ipvs/Kconfig
+++ b/net/netfilter/ipvs/Kconfig
@@ -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---
diff --git a/net/netfilter/ipvs/Makefile b/net/netfilter/ipvs/Makefile
index 38b2723..67f3f43 100644
--- a/net/netfilter/ipvs/Makefile
+++ b/net/netfilter/ipvs/Makefile
@@ -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
diff --git a/net/netfilter/ipvs/ip_vs_ovf.c b/net/netfilter/ipvs/ip_vs_ovf.c
new file mode 100644
index 0000000..4e9458d
--- /dev/null
+++ b/net/netfilter/ipvs/ip_vs_ovf.c
@@ -0,0 +1,87 @@
+/*
+ * IPVS: Overflow-Connection Scheduling module
+ *
+ * Authors: Raducu Deaconu <rhadoo_io@xxxxxxxxx>
+ *
+ * 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, *hw = NULL;
+ int highestw = 0, curentw;
+
+ 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) {
+ curentw = atomic_read(&dest->weight);
+ if ((dest->flags & IP_VS_DEST_F_OVERLOAD) ||
+ atomic_read(&dest->activeconns) > curentw ||
+ curentw == 0)
+ continue;
+ if (!hw || curentw > highestw) {
+ hw = dest;
+ highestw = curentw;
+ }
+ }
+
+ if (hw) {
+ IP_VS_DBG_BUF(6, "OVF: server %s:%u activeconns %d weight %d\n",
+ IP_VS_DBG_ADDR(svc->af, &hw->addr),
+ ntohs(hweight->port),
+ atomic_read(&hw->activeconns),
+ atomic_read(&hw->weight));
+ return hw;
+ }
+
+ 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");
--
1.7.10.4
