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@rponte
rponte / avoid-distributed-transactions.md
Last active October 20, 2025 12:29
THEORY: Distributed Transactions and why you should avoid them (2 Phase Commit , Saga Pattern, TCC, Idempotency etc)

Distributed Transactions and why you should avoid them

  1. Modern technologies won't support it (RabbitMQ, Kafka, etc.);
  2. This is a form of using Inter-Process Communication in a synchronized way and this reduces availability;
  3. All participants of the distributed transaction need to be avaiable for a distributed commit, again: reduces availability.

Implementing business transactions that span multiple services is not straightforward. Distributed transactions are best avoided because of the CAP theorem. Moreover, many modern (NoSQL) databases don’t support them. The best solution is to use the Saga Pattern.

[...]

@odinserj
odinserj / SkipWhenPreviousJobIsRunningAttribute.cs
Last active July 10, 2025 08:54
SkipWhenPreviousJobIsRunningAttribute.cs
// Zero-Clause BSD (more permissive than MIT, doesn't require copyright notice)
//
// Permission to use, copy, modify, and/or distribute this software for any purpose
// with or without fee is hereby granted.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
// OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
@rowanmiller
rowanmiller / Demo.cs
Last active November 5, 2019 09:12
EF6.x | Correlating SQL to code
using System;
using System.Collections.Generic;
using System.Data.Common;
using System.Data.Entity;
using System.Data.Entity.Infrastructure.Interception;
using System.Diagnostics;
using System.IO;
using System.Linq;
namespace Demo
@JonCole
JonCole / ThreadPool.md
Last active May 10, 2025 15:44
Intro to CLR ThreadPool Growth

ThreadPool Growth: Some Important Details

The CLR ThreadPool has two types of threads - "Worker" and "I/O Completion Port" (aka IOCP) threads.

  • Worker threads are used when for things like processing Task.Run(…) or ThreadPool.QueueUserWorkItem(…) methods. These threads are also used by various components in the CLR when work needs to happen on a background thread.
  • IOCP threads are used when asynchronous IO happens (e.g. reading from the network).

The thread pool provides new worker threads or I/O completion threads on demand (without any throttling) until it reaches the "Minimum" setting for each type of thread. By default, the minimum number of threads is set to the number of processors on a system.

Once the number of existing (busy) threads hits the "minimum" number of threads, the ThreadPool will throttle the rate at which is injects new threads to one thread per 500 milliseconds. This means that if your system gets a burst of work needing an IOCP thread, it will proces

@Kartones
Kartones / postgres-cheatsheet.md
Last active October 28, 2025 17:42
PostgreSQL command line cheatsheet

PSQL

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h or --help depending on your psql version):

  • -E: will describe the underlaying queries of the \ commands (cool for learning!)
  • -l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)
namespace Sagas
{
using System;
using System.Collections.Generic;
class Program
{
static ActivityHost[] processes;
@CristinaSolana
CristinaSolana / gist:1885435
Created February 22, 2012 14:56
Keeping a fork up to date

1. Clone your fork:

git clone git@github.com:YOUR-USERNAME/YOUR-FORKED-REPO.git

2. Add remote from original repository in your forked repository:

cd into/cloned/fork-repo
git remote add upstream git://github.com/ORIGINAL-DEV-USERNAME/REPO-YOU-FORKED-FROM.git
git fetch upstream