Oren Eini
Oren Eini is a senior developer / architect, focusing on architecture, data access and best practices. Most often, he is working on building complex business systems using .Net 2.0, NHibernate and Castle's Frameworks, providing training and guidance for the use of Object Relational Mapping, Inversion of Control, Domain Driven Design and other exciting topics. Oren is an active member in several leading Open Source projects, including (but not limited :-) ) NHibernate, Castle and Rhino Mocks.
Ayende @ Rahien | 13 Dec 2013 05:01
Oren Eini writes "....I was interviewed George London for his A* series. This is now online...."
Read more » A* Interview posted
Ayende @ Rahien | 12 Dec 2013 10:00
Oren Eini writes "....Note: I started writing a few minutes after starting the performance test, it took that long to run. As you are probably already aware, we used the Immutable Collections package in Voron. That turned out to be a cause for pretty major performance..."
Read more » More on collection performance, immutability and designing for a specific scenario
Ayende @ Rahien | 11 Dec 2013 10:00
Oren Eini writes "....I was always somewhat baffled that something that was so obviously required so often can be so expensive with RDBMSes. When diving deep into B-Tree implementation I suddenly found it obvious why that is the case. Let us look at the following B-Tree:..."
Read more » The cost of select count(*) from tbl
Ayende @ Rahien | 10 Dec 2013 10:00
Oren Eini writes "....One of the annoying things about doing performance work is that you sometimes feel like you found the problem. You fix it, and another pops out. After the previous run of work, we have tackled two important perf issues: Immutable collections –..."
Read more » HotSpot Shell Game
Ayende @ Rahien | 09 Dec 2013 10:00
Oren Eini writes "....After the issues we run into with immutable structures, I decided that I still wanted to maintain the same guarantees that immutable data structures gave us, but that still maintain the speed of mutable structures. I managed to do that by making..."
Read more » SafeList, SafeDictionary–fast immutable structures
Ayende @ Rahien | 06 Dec 2013 10:00
Oren Eini writes "....Why is the performance of an immutable list over 16 times slower than a standard list? I took a peek at what it was actually doing, and it made a lot of sense. In order to maintain efficient indexing access, the actual storage of the data in the..."
Read more » Immutable collections performance, take II
Ayende @ Rahien | 05 Dec 2013 10:00
Oren Eini writes "....After finding out that a lot of our costs in Voron is actually related to immutable collections, I decided to run some isolated perf tests. 1: private static void Dictionary() 2: { 3: var dic = new Dictionary<object,..."
Read more » Immutable Collections performance
Ayende @ Rahien | 04 Dec 2013 10:00
Oren Eini writes "....Earlier this month I posted our results for the initial performance of Voron. We learned a lot from that, and it led us to do some major refactoring to the codebase. Now, we are back on a more or less stable ground, so it is time to actually see..."
Read more » Fruits of the poisonous tree: Voron performance refactoring
Ayende @ Rahien | 03 Dec 2013 10:00
Oren Eini writes "....I was asked to review the book (and received a free electronic copy). As someone that is very into storage engines, I was quite excited about this. After going over the leveldb codebase, I would finally get to read a real book about how it works...."
Read more » Review: Getting started with LevelDB
Ayende @ Rahien | 02 Dec 2013 10:00
Oren Eini writes "....I got an interesting question from Thomas: How can the OS actually ensure that the write through calls go to disk before returning, when it cannot do the same for fsync. I mean couldn't there still be some driver / raid controller / hard disk doing..."
Read more » The difference between fsync & Write Through, through the OS eyes
