Author Archives | Amichai Lesser
Amichai Lesser - who has written 37 posts on Application Performance Engineering Blog – Shunra Software.
Cloud computing adoption rises so what should you do about it?
I have been meaning to address the impact that cloud computing has on performance engineering but haven’t had the time to rigorously tackle this issue. After all, there are serious implications both for vendors that deliver applications and services from the Cloud as well as enterprises that are rapidly migrating more and more services to [...]
Continue reading...Is Microsoft Quietly Providing an Alternative to WAN Acceleration
Friday, September 4, 2009
As part of our service offerings at Shunra’s professional services, we help our clients analyze the performance ROI of WAN acceleration. We also wrote a best practices paper about it here http://www.shunra.com/uploads/pdf/WAN-acceleration-whitepaper-031909.pdf. Which is why I was very interested in learning about 2 new developments from Microsoft. These developments provide improved performance for branch office [...]
Continue reading...Analyzing and remediating latency sensitive applications part 1
Thursday, August 20, 2009
Examples of latency sensitive applications In the previous post http://www.shunra.com/shunrablog/index.php/2009/08/14/data-center-relocation-questions-and-answers-part-1/ I shared some of the questions that clients typically ask me during the performance analysis service in a data center relocation project. One of the most popular question, especially at the beginning of the project is “which applications are the most sensitive to network latency?”. [...]
Continue reading...Data Center Relocation Questions and Answers Part 1
Friday, August 14, 2009
In my line of work, I get to assist many clients with analyzing the impact of an upcoming data center relocation on the performance of business applications. Many clients don’t know exactly what application performance to expect post the data center move. The main concern is that once all the applications start to operate across [...]
Continue reading...Bandwidth – a glossary post
Thursday, June 25, 2009
Bandwidth constraints: Network capacity, or bandwidth, is the maximal number of bits a network connection or interface can carry at a given period of time. It is measured in bps (bits-per-second), Kbps, Mbps or Gbps. The greater the bandwidth, the greater the number of concurrent application sessions the link can serve (for a given transaction) and [...]
Continue reading...Jitter – a glossary post
Thursday, June 25, 2009
Jitter: Network jitter is the variation in the arrival rate of packets (more specifically, the inter packet gap of subsequent data packets as they arrive over a network). For most types of data applications large gap variations between arrival times (high jitter) are acceptable. For voice or video applications, relatively small jitter can cause perceptible [...]
Continue reading...Packet Loss – a glossary post
Thursday, June 25, 2009
Packet Loss: The term “packet loss” is used to describe the probability of dropping a packet at any point across the network link. The key reasons for packet loss across a network are: When networks get congested over a long period of time the router buffers get saturated which at some point leads to a situation [...]
Continue reading...Network Latency
Thursday, June 25, 2009
In the next couple of posts I will add some glossary definitions that I see repeat in reader’s questions. I will also use these as I describe some of the performance analysis insights we experience in the field. Network Latency/Network Delay One-way network latency is defined as the amount of time it takes for a [...]
Continue reading...Performance Engineering Why so many companies don’t get it – Part 3
Friday, May 29, 2009
In the previous 2 posts we described several ways in which sub optimal performance engineering practices manifest themselves, as well as identified the lack of goal commonality between developers and performance engineers as one of the key reasons behind these sub optimal practices. In this post I want to look at the problem from a [...]
Continue reading...Performance Engineering – Why so many companies don’t get it – Part 2
Thursday, May 7, 2009
Part 2 (for part 1 click here) Anyone who was ever part of a performance engineering process should be able to relate to the following story: “…Version 3.5 of a critical application is scheduled for release in 6 weeks, the latest stable build (internal version) of the application finally made it to the hands of [...]
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Friday, September 11, 2009