Dumping memory on Linux system can be cumbersome especially that the behavior might be different among different GNU/Linux distribution or Linux kernel version. In the early days, the easiest was to dump the memory from the memory device (/dev/mem) but over time the access was more and more restricted in order to avoid malicious process to directly access the kernel memory directly. The kernel option CONFIG_STRICT_DEVMEM was introduced in kernel version 2.6 and upper (2.6.36–2.6.39, 3.0–3.8, 3.8+HEAD). So you'll need to use a Linux kernel module in order to acquire memory.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
--- | |
layout: default | |
--- | |
<div class="blog-index"> | |
{% assign post = site.posts.first %} | |
{% assign content = post.content %} | |
{% include post_detail.html %} | |
</div> |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
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 |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
''' | |
Basic tail command implementation | |
Usage: | |
tail.py filename numlines | |
''' | |
import sys | |
import linecache |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
package main | |
import ( | |
"fmt" | |
"os" | |
"os/signal" | |
"syscall" | |
) | |
func main() { |
Moved to git repository: https://github.com/denji/golang-tls
# Key considerations for algorithm "RSA" ≥ 2048-bit
openssl genrsa -out server.key 2048
# Key considerations for algorithm "ECDSA" ≥ secp384r1
# List ECDSA the supported curves (openssl ecparam -list_curves)
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
sudo gitlab-rails console | |
ApplicationSetting.last.update_attributes(signin_enabled: true) | |
exit | |
sudo gitlab-ctl restart |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
package main | |
import ( | |
"fmt" | |
"net" | |
"time" | |
"bufio" | |
) | |
func handleConnection(conn net.Conn) { |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
# npm using https for git | |
git config --global url."https://github.com/".insteadOf git@github.com: | |
git config --global url."https://".insteadOf git:// | |
# npm using git for https | |
git config --global url."git@github.com:".insteadOf https://github.com/ | |
git config --global url."git://".insteadOf https:// |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
# import config. | |
# You can change the default config with `make cnf="config_special.env" build` | |
cnf ?= config.env | |
include $(cnf) | |
export $(shell sed 's/=.*//' $(cnf)) | |
# import deploy config | |
# You can change the default deploy config with `make cnf="deploy_special.env" release` | |
dpl ?= deploy.env | |
include $(dpl) |
OlderNewer