Comments on: CQRS and user experience http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/ Strong opinions, weakly held Fri, 17 May 2013 09:02:38 +0000 hourly 1 http://wordpress.org/?v=3.4.2 By: Scott Coates http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-5248 Scott Coates Sat, 03 Nov 2012 03:08:00 +0000 http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-5248 This "needs" to be one of the first things mentioned in every Beginner CQRS article. You're right, Jimmy, CQRS is not all that difficult. But when 'experts' start diluting the concept with eventual consistency, async, etc, it becomes pretty confusing. Like Chad Lee mentions, there are obvious scenarios where async makes total sense. For example, on Reddit, if you post a comment you get immediate feedback. However, it can take up to 10 seconds for that comment to truly persist. This “needs” to be one of the first things mentioned in every Beginner CQRS article. You’re right, Jimmy, CQRS is not all that difficult. But when ‘experts’ start diluting the concept with eventual consistency, async, etc, it becomes pretty confusing.

Like Chad Lee mentions, there are obvious scenarios where async makes total sense. For example, on Reddit, if you post a comment you get immediate feedback. However, it can take up to 10 seconds for that comment to truly persist.

]]> By: Tim Smith http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-5085 Tim Smith Mon, 24 Sep 2012 22:15:00 +0000 http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-5085 I would say a majority of the benefits from CQRS are really on the read(query) side more so than the write(command) side. Users will be more understanding of latency when saving work (writes) than they will be when hitting a page to see data(read). I would say a majority of the benefits from CQRS are really on the read(query) side more so than the write(command) side. Users will be more understanding of latency when saving work (writes) than they will be when hitting a page to see data(read).

]]> By: Anonymous http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4993 Anonymous Thu, 13 Sep 2012 12:15:00 +0000 http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4993 RaccoonBlog - it's a CQRS app. https://github.com/ayende/RaccoonBlog RaccoonBlog – it’s a CQRS app. https://github.com/ayende/RaccoonBlog

]]> By: Anonymous http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4977 Anonymous Thu, 13 Sep 2012 01:01:00 +0000 http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4977 Can you guys please recommend a good example with src code? Can you guys please recommend a good example with src code?

]]> By: Anonymous http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4978 Anonymous Thu, 13 Sep 2012 01:01:00 +0000 http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4978 Can you guys please recommend a good example with src code? Can you guys please recommend a good example with src code?

]]> By: Charlie Barker http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4921 Charlie Barker Sun, 09 Sep 2012 23:45:00 +0000 http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4921 So my concern is not that the affected users have to wait it is that the site remains available and responsive to unaffected users. So my concern is not that the affected users have to wait it is that the site remains available and responsive to unaffected users.

]]> By: Charlie Barker http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4920 Charlie Barker Sun, 09 Sep 2012 23:38:00 +0000 http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4920 Async threads are a smart choice as they'll just consume memory on the server whilst they wait for a 3rd party response or IO to complete but they are not free. My experience has been that when pages become un responsive customers start refreshing their browsers and starting fresh applications in effect  they become  mini DOS attackers. The problem only becomes noticible when enough customers are on the site that your server becomes starved of resources to the point it can no longer serve new pages the killer thing is that you are most likely to see this behaviour when your site is at it's busiest. If your selling something then it is likely that this means it is the worst time for your site to be off line or responding slowly. Not all developers need to be concerned by this, low traffic sites that have servers with lots of  RAM will never reach this state. Async threads are a smart choice as they’ll just consume memory on the server whilst they wait for a 3rd party response or IO to complete but they are not free. My experience has been that when pages become un responsive customers start refreshing their browsers and starting fresh applications in effect  they become  mini DOS attackers. The problem only becomes noticible when enough customers are on the site that your server becomes starved of resources to the point it can no longer serve new pages the killer thing is that you are most likely to see this behaviour when your site is at it’s busiest. If your selling something then it is likely that this means it is the worst time for your site to be off line or responding slowly. Not all developers need to be concerned by this, low traffic sites that have servers with lots of  RAM will never reach this state.

]]> By: hahaha http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4916 hahaha Fri, 07 Sep 2012 10:27:00 +0000 http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4916 diu diu

]]> By: João P. Bragança http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4875 João P. Bragança Thu, 30 Aug 2012 09:21:00 +0000 http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4875 I agree with this. I think my intention did not get through, there are supposed to be carriage returns there! I was trying to show the parallels between an eventually consistent cqrs system and the eventually consistent raven indices. I agree with this. I think my intention did not get through, there are supposed to be carriage returns there! I was trying to show the parallels between an eventually consistent cqrs system and the eventually consistent raven indices.

]]> By: Anonymous http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4874 Anonymous Wed, 29 Aug 2012 12:38:00 +0000 http://lostechies.com/jimmybogard/2012/08/23/cqrs-and-user-experience/#comment-4874 Yeah, and perhaps the aggregate boundaries too? Yeah, and perhaps the aggregate boundaries too?

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