TxF

Developer, Meet Server - Transactional NTFS and WCF

Jason Olson — Wed, 04 Apr 2007 21:19:00 GMT

I recently posted the second screencast in my new "Developer, Meet Server" screencast series. This latest screencast covers using Transactional NTFS in a service-oriented environment via WCF.

Enjoy!

Transactional NTFS and Free Disk Space

Jason Olson — Wed, 04 Apr 2007 21:15:00 GMT

Andrew recently watched my screencasts and had some great questions that came up around how Transactional NTFS behaves with the file system. So, I figured I would answer them here. So, if you want to see the context around his questions, check out his post.

Here's the paragraph with the questions:

I wonder what happens to files that never get committed - ala a long running transaction. They have to be taking up file space. Jason says not even Windows Explorer knows about them, but they have to exist somewhere. What if they overflow? Is there a way to clean house? If the poop is invisible, does it still stink?

Great observations and questions Andrew! In the case of a long running, open transaction, the files will exist on the disk. Hence, they are certainly taking up space on the disk. If you have 256 MB of free space on your disk, and try to write 257 MB of data to the disk within a transaction, you will get an "out of space" error like you would outside of a transaction.

Is there a way to clean house? Yes, rollback or commit the transaction. On rollback, any changes made within the transaction are rolled back, and then consequently removed form the disk.

But what if my server crashes in the middle of a transaction. Would I have turds floating around the file system? No, you would not. When an NTFS-formatted volume is mounted in Vista or Windows Server "Longhorn", any transactions that are "in-doubt" (the transaction manager is no longer around and we have no clue on the status of the transaction) will be rolled back automatically, effectively removing all the changes from disk. So, in that sense, you would not have any file turds you have to clean up after a system crash (like you would have if you were doing a "temp file -> rename" type of methodology.

Now, as is usual in transaction systems, you have to be _very_ aware and _very_ cautious of long-running transactions as it could cause some long-term problems that you don't want to deal with. So, there certainly are scenarios where Transactional NTFS just is not a good fit. As tends to be the case with all technology, make sure you are using the right tool for the right job :).

Announcing: New "Developer, Meet Server" Screencast Series

Jason Olson — Fri, 09 Mar 2007 19:28:00 GMT

Welcome everybody to the inaugural, first ever, grand opening, “opening the doors to the public” celebration day kick-off for the new “Developer, Meet Server” screencast series. I am your sincere, humble (as ever), gracious and wonderful host/chef/tour guide Jason Olson.

In this series of screencasts we will be diving through all the various cool developer-oriented enhancements on the Windows Server "Longhorn" platform that developers can leverage to build robust and powerful applications. Specifically, in this first screencast, we will take a quick peek at Transactional NTFS. In future screencasts, we will go into a more detailed look at Transactional NTFS, so think of this as a quick introduction.

The screencast can be found in one of the main tubes on the Intarw3b known as the ever-lovely Channel 9: http://channel9.msdn.com/Showpost.aspx?postid=289816.

So sit back, grab a cup of coffee/tea/InsertYourFavoriteLocalTastyBeverageHere, and enjoy this screencast.

LHS Feature Of The Week #11 - Transactional NTFS + USB Flash Drive

Jason Olson — Fri, 01 Dec 2006 19:03:00 GMT

Hello everyone, and welcome back to the “Feature Of The Week” newsletter. This week, we will revisit a prior Fear Of The Week technology that we discussed in order to show off a cool capability of that technology. If you are a developer wanting to mess around with TxF (Transactional NTFS), you should especially read on :).

Did You Know? Did you know that on Vista, Transactional NTFS will work with an NTFS-formatted USB Flash Drive? It’s true! If you want to play around with Transactional NTFS and how it can interact with SQL, for instance, but you only have one hard drive, you don’t have to worry about Secondary Resource Managers and all that hubbub, gizmos, doodads, and what-cha-ma-call-its. Just pop in that NTFS-formatted USB Flash Drive, and play around until your heart’s content.

Since the USB Flash Drive is not the system drive (well, we hope it’s not the system drive in this case :P), you can circumvent the need for secondary Resource Managers when wanting to test out interoperability scenarios with Transactional NTFS (like TxF + WCF, TxF + SQL, TxF + MSMQ, etc.).

Happy Coding :).

Generic Transactional NTFS Links...

Documentation

Windows SDK

Videos/Webcasts

[Video] Vista Transactional File System
[Webcast] The Revolutionary Vista TxF Infrastructure
[Webcast] Developing Apps For Vista With TxF

Blogs

Transaction Resources List

Jason Olson — Fri, 08 Sep 2006 13:06:00 GMT

I'll be updating this post over time to reflect new resources that are made available regarding the transactions platform in Windows.

Websites:

[Transactions] Transactions Programming Forum - MSDN
[Transactions] Transaction Management in Windows - Microsoft.com
[TxF] TxF Documentation - MSDN

Blogs:

... (Read More)

Other Transaction Resources

Jason Olson — Wed, 06 Sep 2006 14:51:00 GMT

While I'm on the topic of Transaction resources out there, I might as well give a more detailed list. Just off the top of my head, here's the resources you should definitely be checking out if you want to get into transactions on the Windows platform (or even if you are already using transactions on the Windows platform):

Microsoft Sites:

Blogs:

Jim Johnson
Florin Lazar
Well, and I hope, me :).

If I have left out any obvious ones, please let me know so I can update my list :).

Understanding Transactions in .NET

Jason Olson — Wed, 06 Sep 2006 14:43:00 GMT

I came across this article today by Sahil Malik. If you are wanting to get up to speed with System.Transactions in general, as well as how it integrates with ADO.NET, make sure to check it out. He also covers some general concepts regarding transactions as well. So, if you are wanting to understand and be able to explain concepts like Transaction Managers, Resource Managers, Durable Enlistments, etc., also make sure to read it :).

Enjoy!

Using TxF in Vista RC1

Jason Olson — Tue, 05 Sep 2006 14:28:00 GMT

Jim Johnson has a new post about how to use TxF with the new model in Vista RC1. You will obviously need the RC1 bits to mess around with it.

I'm hoping to expand on this topic in the future to show some code samples of using it not only by itself, but also using it with SQL and the like. I'll also have some "context" posts around that describing the architecture and relationships around TxF so you can better understand the articles.

Unil then, go check out Jim's post :).

What is TxF and why do I care?

Jason Olson — Wed, 16 Aug 2006 23:54:00 GMT

A friend of mine made a good comment on my last post about TxF: "what the heck does TxF do and why should developers care?" I hope to answer that question in this post. If you've never heard of TxF, read on. If you have and still don't "grok it", read on. If you just happen to love the wonderful language that is expelled from my tranquil appendages as they dance over the keyboard, then by all means, read on as well :).

So, what is TxF? TxF is the "nick name" for a new technology coming with Vista and Longhorn Server: Transactional NTFS. You may have read about or used logging file systems in the past, and you may have used journaling file systems in the past as well. But TxF is a fully-transactional file system, all built on top of NTFS. And when I say "fully-transactional", I mean it supports full ACID transactions on the file system itself.

Why should you care about TxF? You should care about TxF because... (Read More)

The State Of TxF

Jason Olson — Wed, 09 Aug 2006 13:35:00 GMT

[Usual Disclaimer: my opinions in no way reflect or represent the opinions of my employer]

You'll probably hear me start cheering for TxF after a couple of posts because it is a great technology, but at this point in the ballgame, let's take a step back and take a sobering look at the state of TxF as it exists in post-Beta 2 Vista.

As I've been getting up to speed with TxF, I've realized that there is very little up-to-date information on TxF available (except for an internal presentation that was given at an internal conference). Most likely, any blog posts you'll find on the internet regarding TxF and how to use it are no longer accurate because of the newly revamped API... (Read More)