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Ryuichi Ueda ryuichiueda

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@ryuichiueda
ryuichiueda / swap.c
Created February 15, 2026 02:26
#include <stdlib.h>
#include <unistd.h>
int main(int argc, char const *argv[]) {
int n = atoi(argv[1]);
for(int i=0;i<n;i++) {
char *p = malloc(1024*1024); //1MiBメモリ確保
for(int i=0;i<1024*1024;i+=4096)
p[i] = 111;
}
@ryuichiueda
ryuichiueda / malloc_1gib_time2.c
Created February 14, 2026 01:18
#include <stdlib.h>
#include <unistd.h>
int main() {
char *p = malloc(1024*1024*1024); //1GiBメモリ確保
for(int i=0;i<1024*1024*1024/4096;i++)
p[i] = 111;
exit(0);
}
@ryuichiueda
ryuichiueda / malloc_1gib_time1.c
Created February 14, 2026 01:17
#include <stdlib.h>
#include <unistd.h>
int main() {
char *p = malloc(1024*1024*1024); //1GiBメモリ確保
for(int i=0;i<1024*1024*1024;i+=4096)
p[i] = 111;
exit(0);
}
@ryuichiueda
ryuichiueda / malloc_1gib.c
Last active February 9, 2026 08:30
仮想メモリと確保された物理メモリの容量の違いの調査
#include <stdlib.h>
#include <unistd.h>
int main() {
char *p = malloc(1024*1024*1024); //1GiBメモリ確保
for(int i=0;i<1024*1024;i++) //最初の1MiBにデータ書き込み
p[i] = 111;
sleep(10000); //観察用にプログラムを止める
exit(0);
}
@ryuichiueda
ryuichiueda / result.txt
Last active December 13, 2023 10:21
thread-fork test result
$ cargo run
・・・
1秒後 Child: ""
2秒後 Child: ""
3秒後 Child: ""
4秒後 Child: ""
5秒後 Parent { child: Pid(50794) }: "written"
5秒後 Child: ""
6秒後 Parent { child: Pid(50794) }: "written"
6秒後 Child: ""
@ryuichiueda
ryuichiueda / main.rs
Last active December 13, 2023 10:28
thread-fork test
use std::{time, thread};
use std::sync::{Arc, Mutex};
use std::time::Instant;
use nix::unistd;
use nix::unistd::ForkResult; //懺悔：これいらなかったです（cargo buildするとワーニング出ます。削ってください。）
fn main() {
let s = Arc::new(Mutex::new(String::new())); //Arcの中のMutexの中の文字列がデータ本体です。
let s1 = s.clone();
@ryuichiueda
ryuichiueda / .bash_profile
Created January 8, 2019 04:30
minimum bash_profile for Mac
export CLICOLOR=1
export LSCOLORS=DxGxcxdxCxegedabagacad
alias 'ls=ls -G'
@ryuichiueda
ryuichiueda / .bashrc
Created January 2, 2019 22:57
[ -z "$PS1" ] && return
HISTCONTROL=ignoreboth
shopt -s histappend
HISTSIZE=1000
HISTFILESIZE=2000
shopt -s checkwinsize
if [ -z "$debian_chroot" ] && [ -r /etc/debian_chroot ]; then
debian_chroot=$(cat /etc/debian_chroot)
@ryuichiueda
ryuichiueda / my.terminal
Last active January 2, 2019 00:05
My terminal conf
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>BackgroundAlphaInactive</key>
<real>0.5</real>
<key>BackgroundBlur</key>
<real>0.0</real>
<key>BackgroundBlurInactive</key>
<real>0.48512961647727271</real>
@ryuichiueda
ryuichiueda / update_eng_p22
Last active June 16, 2018 07:00
update_eng_p22
### OLD ###
cd /lib/firmware/brcm/
sudo wget https://github.com/RPi-Distro/firmware-nonfree/raw/master/brcm80211/brcm/brcmfmac43430-sdio.bin -O brcmfmac43430-sdio.bin
sudo wget https://github.com/RPi-Distro/firmware-nonfree/raw/master/brcm80211/brcm/brcmfmac43430-sdio.txt -O brcmfmac43430-sdio.txt
sudo reboot
### NEW ###
cd /lib/firmware/brcm/