Comments for Semergence http://www.semergence.com Semantic Web, Ruby on Rails, and Massive Data Sat, 05 Jul 2008 01:40:48 +0000 http://wordpress.org/?v=2.2.3 Comment on Scalable Counters for Web Applications by admin http://www.semergence.com/2008/06/28/scalable-counters-for-web-applications/#comment-695 admin Mon, 30 Jun 2008 07:24:39 +0000 http://www.semergence.com/2008/06/28/scalable-counters-for-web-applications/#comment-695 Hi Peter, Yes, from Manlius. :) Second, I'd caution about the message queue. Where are you going to persist those messages? Are you concerned about possibly losing them? Third, if you are using Java, you want to look at AtomicLong. Fourth, if you have a group of message beans (man, that's old school. you haven't switched to Spring yet? :) are they going to write to the same counter? If so, you have the same contention issue. Or are you going to use partitioned counters? Hi Peter,

Yes, from Manlius. :)

Second, I’d caution about the message queue. Where are you going to persist those messages? Are you concerned about possibly losing them?

Third, if you are using Java, you want to look at AtomicLong.

Fourth, if you have a group of message beans (man, that’s old school. you haven’t switched to Spring yet? :) are they going to write to the same counter? If so, you have the same contention issue. Or are you going to use partitioned counters?

]]> Comment on Scalable Counters for Web Applications by Peter Daly http://www.semergence.com/2008/06/28/scalable-counters-for-web-applications/#comment-693 Peter Daly Mon, 30 Jun 2008 01:46:52 +0000 http://www.semergence.com/2008/06/28/scalable-counters-for-web-applications/#comment-693 Here's how I'd tackle this problem...although my mind is thinking in terms of Java solution. First, you need a single counting entity. Static session bean type thing. When it is created, it loads an initial count from a persistent store and sets in it in a variable. When it is asked to get/increment count it would (in a synchronized/locking method) 1. Increment the counter variable 2. Throw a (small) "hit" event onto a message queue 3. Return the new value Problem 1 solved..how to count fast in a synchronized manor. Problem 2 is left...persisting the data. There are a few options here. The most simple option would to have a group of message beans read the queue and write the records to a DB. This method should be able to scale very well. For outputting a new "hit" value, no DB read is required. A fail-over system could be implemented to handle counts for downtime situations with no data loss. Thanks for giving my brain a simple yet complex problem to crunch on this evening. Are you the Seth Ladd from Manlius, NY? Peter Daly Here’s how I’d tackle this problem…although my mind is thinking in terms of Java solution.

First, you need a single counting entity. Static session bean type thing.

When it is created, it loads an initial count from a persistent store and sets in it in a variable.

When it is asked to get/increment count it would (in a synchronized/locking method)
1. Increment the counter variable
2. Throw a (small) “hit” event onto a message queue
3. Return the new value

Problem 1 solved..how to count fast in a synchronized manor.

Problem 2 is left…persisting the data. There are a few options here. The most simple option would to have a group of message beans read the queue and write the records to a DB.

This method should be able to scale very well. For outputting a new “hit” value, no DB read is required.

A fail-over system could be implemented to handle counts for downtime situations with no data loss.

Thanks for giving my brain a simple yet complex problem to crunch on this evening.

Are you the Seth Ladd from Manlius, NY?

Peter Daly

]]> Comment on Proposed Enhancements For Web Browsers by drewp http://www.semergence.com/2008/06/10/proposed-enhancements-for-web-browsers/#comment-689 drewp Tue, 17 Jun 2008 06:17:06 +0000 http://www.semergence.com/2008/06/10/proposed-enhancements-for-web-browsers/#comment-689 A more browser-centered solution that doesn't involve changing HTML (!) would be to make a way to temporarily jump back to a designated tab or tabs. I could use that kind of solution on any existing website, not just ones who use your extension. And, the same system would work if there's a little bit more than some commands that I want to easily jump to, e.g. a chat window. Example implementation: when I'm hovering on a tab and I press ctrl-0, add a [0] to the tab label. I can make 10 such markers with ctrl-0..9. When I press ctrl-0 later, render that [0] tab's page on top of my current page, inset from the edges a little. At the top of the inset render, write "Showing [title of tab], ctrl-0 to close". That will reinforce the idea that this is meant for temporary usage, and that the page I was previously viewing is just underneath the [0] page. I.e. there's a visible stack of two pages. A more browser-centered solution that doesn’t involve changing HTML (!) would be to make a way to temporarily jump back to a designated tab or tabs. I could use that kind of solution on any existing website, not just ones who use your extension. And, the same system would work if there’s a little bit more than some commands that I want to easily jump to, e.g. a chat window.

Example implementation: when I’m hovering on a tab and I press ctrl-0, add a [0] to the tab label. I can make 10 such markers with ctrl-0..9. When I press ctrl-0 later, render that [0] tab’s page on top of my current page, inset from the edges a little. At the top of the inset render, write “Showing [title of tab], ctrl-0 to close”. That will reinforce the idea that this is meant for temporary usage, and that the page I was previously viewing is just underneath the [0] page. I.e. there’s a visible stack of two pages.

]]> Comment on Proposed Enhancements For Web Browsers by John Hume http://www.semergence.com/2008/06/10/proposed-enhancements-for-web-browsers/#comment-687 John Hume Sat, 14 Jun 2008 17:53:17 +0000 http://www.semergence.com/2008/06/10/proposed-enhancements-for-web-browsers/#comment-687 The same context menu could come up when right-clicking a window button on a task bar, for GUIs that have such things. (I can't think of a place where that would appear in OS X.) I'd also still like to see browsers incorporate buttons for LINK tags specifying next page, previous page, etc. The same context menu could come up when right-clicking a window button on a task bar, for GUIs that have such things. (I can’t think of a place where that would appear in OS X.)

I’d also still like to see browsers incorporate buttons for LINK tags specifying next page, previous page, etc.

]]> Comment on Nest Those Rails Resources Or Make Baby Semantic Web Cry by admin http://www.semergence.com/2008/04/02/nest-those-rails-resources-or-make-baby-semantic-web-cry/#comment-686 admin Sat, 14 Jun 2008 16:55:21 +0000 http://www.semergence.com/2008/04/02/nest-those-rails-resources-or-make-baby-semantic-web-cry/#comment-686 Really? There's no redirect for me. Really? There’s no redirect for me.

]]> Comment on Nest Those Rails Resources Or Make Baby Semantic Web Cry by Marcelo http://www.semergence.com/2008/04/02/nest-those-rails-resources-or-make-baby-semantic-web-cry/#comment-685 Marcelo Sat, 14 Jun 2008 08:51:36 +0000 http://www.semergence.com/2008/04/02/nest-those-rails-resources-or-make-baby-semantic-web-cry/#comment-685 How about a redirect though? twitter.com/home, which when user logged in, goes to twitter.com/some_user How about a redirect though?
twitter.com/home, which when user logged in, goes to
twitter.com/some_user

]]> Comment on Proposed Enhancements For Web Browsers by Justin http://www.semergence.com/2008/06/10/proposed-enhancements-for-web-browsers/#comment-683 Justin Thu, 12 Jun 2008 16:43:06 +0000 http://www.semergence.com/2008/06/10/proposed-enhancements-for-web-browsers/#comment-683 Isn't IE8 doing something with context menu's? I don't think they are tackling this exact situation, but I know it was something like that. IE, doing something right? It can't be true!!! >;) Isn’t IE8 doing something with context menu’s? I don’t think they are tackling this exact situation, but I know it was something like that.

IE, doing something right? It can’t be true!!! >;)

]]> Comment on Proposed Enhancements For Web Browsers by Colm Kennedy http://www.semergence.com/2008/06/10/proposed-enhancements-for-web-browsers/#comment-682 Colm Kennedy Wed, 11 Jun 2008 11:33:38 +0000 http://www.semergence.com/2008/06/10/proposed-enhancements-for-web-browsers/#comment-682 lot to be said for just sticking to just? documents [...] lot to be said for just sticking to just? documents […]

]]> Comment on Google’s App Engine To Force Me To Learn Django by Aytas http://www.semergence.com/2008/04/07/time-to-learn-django/#comment-615 Aytas Thu, 24 Apr 2008 04:27:04 +0000 http://www.semergence.com/2008/04/07/time-to-learn-django/#comment-615 Nice post. AppEngine is exciting enough for me. BTW I see that you are interested in OLAP. Are you working on anything specific? -Aytas. Nice post. AppEngine is exciting enough for me. BTW I see that you are interested in OLAP. Are you working on anything specific?

-Aytas.

]]> Comment on RSpec is Fun by Nodalities » Blog Archive » This Week’s Semantic Web http://www.semergence.com/2008/03/19/rspec-is-fun/#comment-597 Nodalities » Blog Archive » This Week’s Semantic Web Thu, 17 Apr 2008 16:53:56 +0000 http://www.semergence.com/2008/03/19/rspec-is-fun/#comment-597 [...] RSpec is Fun [...] […] RSpec is Fun […]

]]>