calvin2021y

Podman with docker-compose on MacOS.

Podman an alternative to Docker Desktop on MacOS

Getting podman installed and started is super easy.
Just use brew to install it.

> brew install podman

Now since podman uses a VM just like the Docker Client on MacOS we need to initialize that and start it.

calvin2021y

# 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://

calvin2021y

#
# CORS header support
#
# One way to use this is by placing it into a file called "cors_support"
# under your Nginx configuration directory and placing the following
# statement inside your **location** block(s):
#
#   include cors_support;
#
# As of Nginx 1.7.5, add_header supports an "always" parameter which

calvin2021y

// 1) "Tables of linear congruential generators of different sizes and good lattice structure" (1999), Pierre L'Ecuyer
// 2) Pre-print version of (3)  (https://arxiv.org/abs/2001.05304)
// 3) "Computationally easy, spectrally good multipliers for congruential pseudorandom number generators" (2021), Guy L. Steele Jr. & Sebastiano Vigna (https://onlinelibrary.wiley.com/doi/epdf/10.1002/spe.3030)

// inline comment number is bit width of constant

const uint32_t lcg_mul_k_table_32[] =
{
  // (3) Table 4 LCGs
  0x0000d9f5, // 16      

calvin2021y

Install dnsmasq and configure for *.dev.local domains

$ brew install dnsmasq
$ vim /usr/local/etc/dnsmasq.conf

Reload configuration and clear cache

# Copy the daemon configuration file into place.
$ sudo cp $(brew list dnsmasq | grep /homebrew.mxcl.dnsmasq.plist$) /Library/LaunchDaemons/

$ sudo launchctl unload /Library/LaunchDaemons/homebrew.mxcl.dnsmasq.plist

calvin2021y

---

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Note: these instructions are for pre-Sierra MacOS. Sierra (10.12) and newer users see https://gist.github.com/gravitylow/fb595186ce6068537a6e9da6d8b5b96d by @gravitylow

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If you are getting this in gdb on OSX while trying to run a program:

calvin2021y

Sample config for 2 million web socket connection

    sysctl -w fs.file-max=12000500
    sysctl -w fs.nr_open=20000500
    # Set the maximum number of open file descriptors
    ulimit -n 20000000

    # Set the memory size for TCP with minimum, default and maximum thresholds 
 sysctl -w net.ipv4.tcp_mem='10000000 10000000 10000000'

calvin2021y

FFmpeg Minimal Build for RTMP Streaming

This tutorial will work you through steps of configuring an FFmpeg build tailored for RTMP streaming on macOS. At first I think of making it support general live streaming, with additional protocols like HLS, but to keep things simple let's stick with RTMP for now. (Anyway, I do include HLS in the protocol list as well as some related bitstream filters but it's untested.)

Goal

The built FFmpeg executable should

calvin2021y

Full Source Code: https://github.com/varunon9/DynamicWallpaper/tree/always_running_service

Steps-

1. Create a Foreground Service (MyService.java)
2. Create a Manifest registered Broadcast Receiver (MyReceiver.java) which will start your Foreground Service
3. In onDestroy lifecycle of MyService, send a broadcast intent to MyReceiver
4. Launch the MyService on app start from MainActivity (see step 8)
5. With above 4 steps, MyService will always get re-started when killed as long as onDestroy of Service gets called
6. onDestroy method of Service is not always guaranteed to be called and hence it might not get started again

calvin2021y

$ apk add --no-cache curl
$ echo "cgroup /sys/fs/cgroup cgroup defaults 0 0" >> /etc/fstab

$ cat > /etc/cgconfig.conf <<EOF
mount {
  cpuacct = /cgroup/cpuacct;
  memory = /cgroup/memory;
  devices = /cgroup/devices;
  freezer = /cgroup/freezer;