Category Archives: Messaging

ACID 2.0 in action

One of the comments in my last post on message idempotency asked about message ordering. This is part of a larger issue that I’ve run into recently around turning two-phase commits off. When looking at mutating state through interactions, typically … Continue reading 

Also posted in SOA | 5 Comments

(Un) Reliability in messaging: idempotency and de-duplication

In my post on ditching two-phase commits, I introduced the problem of trying to listen and talk at the same time. Essentially, people typically do two-phased commits in messaging systems because they want to deal with messages “exactly once”. But … Continue reading 

Also posted in SOA | 7 Comments

Saga patterns: wrap up

Posts in this series: Observer pattern Controller pattern Pattern variations Scaling sagas Routing slips NServiceBus sagas are a simple yet flexible tool to achieve a variety of end goals. Whether it’s orchestration, choreography, business activity monitoring, or just other long-running … Continue reading 

Also posted in NServiceBus | 3 Comments

Ditching two-phased commits

I’ve had a love-hate relationship with two-phased commits during my years with messaging. Even if MSDTC was free to set up, it doesn’t come free in terms of throughput. Most people run into 2PC in messaging because because queueing systems … Continue reading 

Also posted in SOA | 17 Comments

Messages, data and types

One concern I receive quite a bit from folks new to messaging, especially those coming from SOAP and WCF land, is how to preserve the convenience of proxy classes and data contracts that can be shared amongst multiple clients. The … Continue reading 

Also posted in SOA | 7 Comments

Saga alternatives – routing slips

In the last few posts on sagas, we looked at a variety of patterns of modeling long-running business transactions. However, the general problem of message routing doesn’t always require a central point of control, such as is provided with the … Continue reading 

Also posted in NServiceBus | 3 Comments

Scaling NServiceBus Sagas

When looking at NServiceBus sagas (process managers), especially at high volume of messages, we often run into two main problems: Deadlocks Starvation This is because of the fundamental (default) design of sagas is that: A single saga shares a single … Continue reading 

Also posted in NServiceBus, SOA | 7 Comments

Saga implementation patterns – variations

In the previous couple of posts, I looked at the two main patterns I run into when looking at sagas: Command-oriented (request/response) in the Controller pattern Event-oriented (pub/sub) in the Observer pattern Of course, these aren’t the only ways our … Continue reading 

Also posted in NServiceBus, SOA | 7 Comments

Saga implementation patterns – Controller

In the previous post on saga implementation patterns, we looked at the Observer pattern. In that pattern, the saga was a passive participant in the business transaction, similar to how many fast food restaurants fulfill orders. But not all food … Continue reading 

Also posted in NServiceBus, SOA | 18 Comments

Saga implementation patterns – Observer

NServiceBus sagas, itself an implementation of the Process Manager pattern, often takes one of two main forms when implemented. It’s not a cut and dry distinction, but in general, I’ve found that saga implementations typically fall into one or the … Continue reading 

Also posted in NServiceBus, SOA | 12 Comments