Julian Anastasov 7106f94330 ipvs: allow connection reuse for unconfirmed conntrack ... [ Upstream commit f0a5e4d7a5 ] YangYuxi is reporting that connection reuse is causing one-second delay when SYN hits existing connection in TIME_WAIT state. Such delay was added to give time to expire both the IPVS connection and the corresponding conntrack. This was considered a rare case at that time but it is causing problem for some environments such as Kubernetes. As nf_conntrack_tcp_packet() can decide to release the conntrack in TIME_WAIT state and to replace it with a fresh NEW conntrack, we can use this to allow rescheduling just by tuning our check: if the conntrack is confirmed we can not schedule it to different real server and the one-second delay still applies but if new conntrack was created, we are free to select new real server without any delays. YangYuxi lists some of the problem reports: - One second connection delay in masquerading mode: https://marc.info/?t=151683118100004&r=1&w=2 - IPVS low throughput #70747 https://github.com/kubernetes/kubernetes/issues/70747 - Apache Bench can fill up ipvs service proxy in seconds #544 https://github.com/cloudnativelabs/kube-router/issues/544 - Additional 1s latency in `host -> service IP -> pod` https://github.com/kubernetes/kubernetes/issues/90854 Fixes: f719e3754e ("ipvs: drop first packet to redirect conntrack") Co-developed-by: YangYuxi <yx.atom1@gmail.com> Signed-off-by: YangYuxi <yx.atom1@gmail.com> Signed-off-by: Julian Anastasov <ja@ssi.bg> Reviewed-by: Simon Horman <horms@verge.net.au> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2020-08-19 08:14:56 +02:00
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acpi	x86: ACPI: fix CPU hotplug deadlock	2020-04-23 10:30:20 +02:00
asm-generic	x86, vmlinux.lds: Page-align end of ..page_aligned sections	2020-07-29 10:16:58 +02:00
clocksource
crypto	crypto: af_alg - fix use-after-free in af_alg_accept() due to bh_lock_sock()	2020-07-09 09:37:10 +02:00
drm
dt-bindings
keys	KEYS: Don't write out to userspace while holding key semaphore	2020-04-23 10:30:24 +02:00
kvm
linux	tracepoint: Mark __tracepoint_string's __used	2020-08-19 08:14:47 +02:00
math-emu
media
memory
misc
net	ipvs: allow connection reuse for unconfirmed conntrack	2020-08-19 08:14:56 +02:00
pcmcia
ras
rdma	RDMA/core: Fix double destruction of uobject	2020-06-03 08:19:43 +02:00
scsi
soc
sound	ASoC: rt5670: Add new gpio1_is_ext_spk_en quirk and enable it on the Lenovo Miix 2 10	2020-07-29 10:16:58 +02:00
target	scsi: target: fix hang when multiple threads try to destroy the same iscsi session	2020-04-21 09:03:11 +02:00
trace	rxrpc: Fix trace string	2020-07-22 09:32:13 +02:00
uapi	wireless: Use offsetof instead of custom macro.	2020-08-05 10:06:01 +02:00
video
xen