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# If you're looking into the C10M problem (10 million concurrent connections)
# you might want to play with DPDK (Originally proprietry Intel, now open source)
#
# C10M: http://c10m.robertgraham.com/
# DPDK: http://dpdk.org/
#
# This is a quick summary how to install dpdk on ubuntu
# running inside virtualbox on a mac
# On my Mac:
@jboner
jboner / latency.txt
Last active August 26, 2025 09:23
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@kfox
kfox / sysctl.conf
Created February 29, 2012 17:32
Linux kernel tuning settings for large number of concurrent clients
# Kernel sysctl configuration file for Red Hat Linux
#
# For binary values, 0 is disabled, 1 is enabled. See sysctl(8) and
# sysctl.conf(5) for more details.
# Controls source route verification
net.ipv4.conf.default.rp_filter = 1
# Do not accept source routing
net.ipv4.conf.default.accept_source_route = 0