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@gg7
gg7 / 01-upstart-normal.sh
Last active May 15, 2016 19:42
leaking orphaned processes
root@u1404:~# cat /etc/init/orph.conf
description "orphaned process / process group test"
respawn
script
sleep 9999 &
sleep 4444
end script
root@u1404:~# start orph
orph start/running, process 3269
@gg7
gg7 / docker-veth.sh
Last active October 28, 2016 21:28
Retrive Docker container network veth pair device on host machine
#!/bin/bash
set -o errexit
set -o nounset
set -o pipefail
# set -o noclobber
# set -o xtrace
cd -- "$(dirname "$0")"
@gg7
gg7 / cd.md
Last active February 28, 2017 00:43
Continuous delivery with Kubernetes
@gg7
gg7 / iptables-dnat-ssh-tunnel.md
Last active November 9, 2017 17:52
SSH tunnel + iptables DNAT + Docker containers

Tell the kernel to route traffic to 127.0.0.0/8:

root@george:~# sysctl -w net.ipv4.conf.docker0.route_localnet=1

(You might need to do this for additional interfaces -- works for me)

Make sure your INPUT chain of the filter table will accept the connection:

root@george:~# iptables -I INPUT -i docker+ -d 127.0.0.0/8 -j ACCEPT
@gg7
gg7 / ip_vs_sch.c
Created December 8, 2017 19:06 — forked from SaveTheRbtz/ip_vs_sch.c
Consistent source hashing scheduler for IPVS (SH-derivative, GPL)
/*
* IPVS: Source Consistent Hashing scheduling module
*
* Authors: Jonathan Lee <jonlee@dropbox.com>
*
* Changes:
*
*/
#define KMSG_COMPONENT "IPVS"
@gg7
gg7 / hfsc-shape.sh
Created December 11, 2017 23:15 — forked from eqhmcow/hfsc-shape.sh
HFSC - linux traffic shaping's best kept secret
#!/bin/bash
# As the "bufferbloat" folks have recently re-discovered and/or more widely
# publicized, congestion avoidance algorithms (such as those found in TCP) do
# a great job of allowing network endpoints to negotiate transfer rates that
# maximize a link's bandwidth usage without unduly penalizing any particular
# stream. This allows bulk transfer streams to use the maximum available
# bandwidth without affecting the latency of non-bulk (e.g. interactive)
# streams.
#!/bin/bash
set -o errexit
set -o nounset
set -o pipefail
empty_regex='\s1500\s+0\s+0\s+0\s+0\s+0\s+0\s+0\s+0\s+0\s+BMU'
o=$(sudo cl-netstat | grep -Pv "$empty_regex")
echo "$o" | grep -P '^(Iface|---)'
@gg7
gg7 / kernel-changes.txt
Created August 1, 2018 09:24
Notable new kernel features for servers since 3.10 (released 30 Jun 2013)
3.11 -- O_TMPFILE open(2) flag, Low latency network polling,
3.12 -- Better Out-Of-Memory handling
3.13 -- nftables, improved NUMA performance, improved page table access scalability in hugepage workloads
3.14 -- SCHED_DEADLINE, KASR, TCP automatic corking
3.15 -- AVX-512 support
3.18 -- overlayfs
4.1 -- MPLS
4.3 -- membarrier(2), limiting the number of PIDs in cgroups
4.4 -- TCP listener handling completely lockless
4.5 -- MADV_FREE for madvise(2), Better epoll multithread scalability
Ranked by discretionary assets managed in hedge funds worldwide, in millions, as of June 30, 2018, unless otherwise noted.
Rank Manager Assets Change from 2017
1 Bridgewater Associates $132,756 7.9%
2 AQR Capital Mgmt. $83,700 9.2%
3 Man Group $59,100 11.3%
4 Renaissance Technologies $57,000 17.3%
5 Two Sigma Inv./Two Sigma Advisers $38,800 9.6%
6 Millennium Mgmt. $35,314 2.7%
7 Elliott Management $35,000 7.0%
@gg7
gg7 / fast-forward.js
Created November 27, 2018 16:56 — forked from ChrisFulstowAGL/fast-forward.js
Video playback speed bookmarklet
javascript:var s = prompt("Playback speed?"); document.getElementsByTagName("video")[0].playbackRate = parseFloat(s);