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motte / latency.txt
Created October 3, 2020 21:09 — forked from jboner/latency.txt
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
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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
@motte
motte / kubernetes-gencerts.sh
Created September 21, 2020 00:14 — forked from fauberso/kubernetes-gencerts.sh
Generates self-signed tls secrets for kubernetes. Run this with e.g. 'kubernetes-gencerts microk8s.local', then install the secrets with 'kubectl apply -f microk8s.local.yaml'
#!/bin/bash
HOSTNAME=${1:-localhost}
openssl req -newkey rsa:4096 -nodes -keyout $HOSTNAME.key -x509 -days 3650 -out $HOSTNAME.crt
echo "apiVersion: v1
kind: Secret
metadata:
name: $HOSTNAME.tls
namespace: default
type: kubernetes.io/tls
data: