Xiaofan Hu bom-d-van

About

I faced bandwidth issues between a WG Peer and a WG server. Download bandwidth when downloading from WG Server to WG peer was reduced significantly and upload bandwidth was practically non existent.
I found a few reddit posts that said that we need to choose the right MTU. So I wrote a script to find an optimal MTU.
Ideally I would have liked to have run all possible MTU configurations for both WG Server and WG Peer but for simplicity I choose to fix the WG Server to the original 1420 MTU and tried all MTUs from 1280 to 1500 for the WG Peer.

Testing

On WG server, I started an iperf3 server
On WG peer, I wrote a script that does the following:
- wg-quick down wg0
Edit MTU in the /etc/wireguard/wg0.conf file

Ubuntu: Install Kernel and Set GRUB Default Kernel

Install Kernel

Install the default kernel:

sudo apt install linux-generic

Set GRUB Default Kernel

Find entrance from /boot/grub/grub.cfg
- Get the $menuentry_id_option:

In order to compile a fully static binary when using Cgo you'll need to link in a C library like musl.

I find it convenient to have a Docker image ready for building these artifacts.

FROM golang
RUN wget https://musl.libc.org/releases/musl-1.2.5.tar.gz && \
   tar -xzf musl-1.2.5.tar.gz && \
   cd musl-1.2.5 && \
 ./configure --enable-static --disable-shared &amp;&amp; \

Blog 2020/9/1

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Quick-n-dirty QEMU script to spin up Debian on various CPU's

updated 2025/4/2

Various ways to restart pods

Restart deployment

The most gracefull way is to trigger a restart for the deployment. In this case, a pod will only be terminated once the new pod is ready. It will slowly replace all pods one after the other.

kubectl rollout restart deployment <deployment-name>

	// Command iossize predicts the impact
	// on memory usage of changes to the binary.
	//
	// This implementation uses dyldinfo to determine
	// exactly how much memory the dynamic linker will dirty
	// as part of launching the executable.
	//
	// It is not perfect. There are multiple sources of dirty pages:
	//
	// 1. dynamic loader rebase/relocs due to our code

	// This can grow a Robin Hood linear probing hash table near word-at-a-time memcpy speeds. If you're confused why I use 'keys'
	// to describe the hash values, it's because my favorite perspective on Robin Hood (which I learned from Paul Khuong)
	// is that it's just a sorted gap array which is MSB bucketed and insertion sorted per chain:
	// https://pvk.ca/Blog/2019/09/29/a-couple-of-probabilistic-worst-case-bounds-for-robin-hood-linear-probing/
	// The more widely known "max displacement" picture of Robin Hood hashing also has strengths since the max displacement
	// can be stored very compactly. You can see a micro-optimized example of that here for small tables where the max displacement
	// can fit in 4 bits: Sub-nanosecond Searches Using Vector Instructions, https://www.youtube.com/watch?v=paxIkKBzqBU
	void grow(Table *table) {
	u64 exp = 64 - table->shift;
	// We grow the table downward in place by a factor of 2 (not counting the overflow area at table->end).

	// RCL 05 June 2021

	/*
	verify with `openssl pkey -in <privatekey>` or `openssl pkey -in <privatekey> -pubout`
	the latter should match the publickey
	*/

	package main

	import (

	/*
	* m1racle-poc: a basic proof of concept for the M1RACLES vulnerability in the Apple M1.
	*
	* This program allows you to read and write the state of the s3_5_c15_c10_1 CPU register.
	*
	* Please visit m1racles.com for more information.
	*
	* Licensed under the MIT license.
	*/

	package main

	import (
	"context"
	"fmt"
	"io"
	"net/http"
	"os"
	"os/signal"
	"syscall"