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leepro / latency.txt
Created January 23, 2018 23:33 — forked from jboner/latency.txt
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers
--------------------------
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
@leepro
leepro / latency.txt
Created January 23, 2018 23:33 — forked from jboner/latency.txt
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers
--------------------------
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
@leepro
leepro / memory_layout.md
Created January 8, 2018 21:52 — forked from CMCDragonkai/memory_layout.md
Linux: Understanding the Memory Layout of Linux Executables

Understanding the Memory Layout of Linux Executables

Required tools for playing around with memory:

  • hexdump
  • objdump
  • readelf
  • xxd
  • gcore
@leepro
leepro / memory_layout.md
Created January 8, 2018 21:52 — forked from CMCDragonkai/memory_layout.md
Linux: Understanding the Memory Layout of Linux Executables

Understanding the Memory Layout of Linux Executables

Required tools for playing around with memory:

  • hexdump
  • objdump
  • readelf
  • xxd
  • gcore
@leepro
leepro / client.go
Created December 19, 2017 05:45 — forked from hakobe/client.go
golang unix domain socket
package main
import (
"io"
"log"
"net"
"time"
)
func reader(r io.Reader) {
@leepro
leepro / groupcache.go
Created December 18, 2017 07:44 — forked from fiorix/groupcache.go
Simple groupcache example
// Simple groupcache example: https://github.com/golang/groupcache
// Running 3 instances:
// go run groupcache.go -addr=:8080 -pool=http://127.0.0.1:8080,http://127.0.0.1:8081,http://127.0.0.1:8082
// go run groupcache.go -addr=:8081 -pool=http://127.0.0.1:8081,http://127.0.0.1:8080,http://127.0.0.1:8082
// go run groupcache.go -addr=:8082 -pool=http://127.0.0.1:8082,http://127.0.0.1:8080,http://127.0.0.1:8081
// Testing:
// curl localhost:8080/color?name=red
package main
import (
@leepro
leepro / groupcache.go
Created December 18, 2017 07:44 — forked from fiorix/groupcache.go
Simple groupcache example
// Simple groupcache example: https://github.com/golang/groupcache
// Running 3 instances:
// go run groupcache.go -addr=:8080 -pool=http://127.0.0.1:8080,http://127.0.0.1:8081,http://127.0.0.1:8082
// go run groupcache.go -addr=:8081 -pool=http://127.0.0.1:8081,http://127.0.0.1:8080,http://127.0.0.1:8082
// go run groupcache.go -addr=:8082 -pool=http://127.0.0.1:8082,http://127.0.0.1:8080,http://127.0.0.1:8081
// Testing:
// curl localhost:8080/color?name=red
package main
import (
@leepro
leepro / groupcache.go
Created December 18, 2017 07:44 — forked from fiorix/groupcache.go
Simple groupcache example
// Simple groupcache example: https://github.com/golang/groupcache
// Running 3 instances:
// go run groupcache.go -addr=:8080 -pool=http://127.0.0.1:8080,http://127.0.0.1:8081,http://127.0.0.1:8082
// go run groupcache.go -addr=:8081 -pool=http://127.0.0.1:8081,http://127.0.0.1:8080,http://127.0.0.1:8082
// go run groupcache.go -addr=:8082 -pool=http://127.0.0.1:8082,http://127.0.0.1:8080,http://127.0.0.1:8081
// Testing:
// curl localhost:8080/color?name=red
package main
import (
@leepro
leepro / md5_dedup.sh
Created October 26, 2017 02:30
#!/bin/bash
rm -f ./tmp
while read line; do echo $line | md5sum | awk '{print $1}' >> ./tmp; done < ./input.txt
paste ./tmp ./test | sort --parallel=8 | uniq > ./result.txt
@leepro
leepro / jit.c
Created April 21, 2017 05:41 — forked from skeeto/jit.c
Basic JIT
/* http://redd.it/2z68di */
#define _BSD_SOURCE // MAP_ANONYMOUS
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <sys/mman.h>
#define PAGE_SIZE 4096