Welcome!

Weblogic Authors: Yeshim Deniz, Elizabeth White, Michael Meiner, Michael Bushong, Avi Rosenthal

Related Topics: Weblogic

Weblogic: Article

WebLogic Performance: Pursuit of Speed Isn't Everything

Keeping your bottlenecks for the candles

"High performance" is what everybody strives for when putting together a new system. Technical folk often spend hours hung up on the raw speed of their code, and a certain machismo can be derived from shaving milliseconds off that pesky transaction that is the latest pride and joy. Often, this time is not very well spent.

In the pursuit of raw speed, not only does readable code often get substituted for the obscure (usually to no avail - optimizing compilers are pretty good these days), thus causing a maintenance headache in the future, but in many cases the performance metric being optimized is a pretty uninteresting one in the overall scheme of things. Many people develop a blinkered focus on the amount of time it takes for one request to do a round-trip - "That debit transaction just took 20ms to debit £500 from a savings account, whoopee!!"

For a transactional system, the throughput of the system is generally far more interesting than the absolute speed of a request (although, that said, there is mostly some constraint that must be met around the time it takes to execute transactions). Throughput is a measure of the amount of work that can be driven through the system while achieving the targets for response time. More work, of course, is partly driven by more clients requesting transactions in the system. The bonus amusement factor here is that the response time and the number of clients are not independent variables - the more clients throwing work at the system, the more likely it becomes that the individual transactions will take longer. Thus, the maximum throughput of a system governs (for a given deployment environment) how many clients can throw transactions into the system at some desired rate, keeping the response time of some fraction of the transactions (say, 90 percent) within the required limit. Having arrived at this conclusion, hours of fun ensue changing various system parameters (number of execute threads, number of database connections, number of machines, etc.) in attempting to predict what the production setup needs to look like to meet the required service levels and to optimize use of server resources.

In fact, it should not be at all surprising to anyone who is using an application server that the individual round-trip time of a single transaction is of little interest. Clearly, the way to optimize that is to have as short a code path as possible between the client and the back end it affects - sticking layers of application server infrastructure between the client and the back end is clearly not going to shorten the codepath. It does, however, improve the throughput. It does this mainly by sharing scarce server-side resources (database connections, threads, etc.) among the population of clients. With the simple-minded short codepath route to performance, you will end up with a one-to-one relationship between the number of clients and the resources consumed on the server, and once all the server's resources are consumed, you have reached a performance bottleneck and the throughput can be increased no further until you can scrape together some more resources to share out. What the application server is doing in effect is economizing the number of resources consumed on the server side by sharing them out among a population of clients (at the expense of a longer codepath, implying marginally increased transaction round-trip time), thereby increasing the maximum possible throughput of the system. At this point, everyone's favorite knee-jerk reaction: "I don't use transactions, they slow things down" can be usefully reviewed.

By now we have seen a system rushing as many requests as possible through a limited set of server resources. It goes without saying that all of these requests must achieve the correct results - that is, the result of any one of the requests executing on its own should be the same if the request is executed in parallel with lots of other requests (or the requests should be isolated, to use the parlance and yes, isolation is the "I" in ACID, and transactions are what give you ACID properties). So the cost of using XA transactions is a little absolute performance, but the benefit is that the results of your transactions are correct. You can rest easy at night knowing that withdrawals from your bank account aren't going to go screwy under some obscure loading conditions IF your bank is using XA!

This discussion takes place completely at the data level - XA is all about database transactions. Each transaction locks the data in the database until the transaction is complete, whereupon the results become visible to the waiting world. Transactions cause bottlenecks when multiple requests are trying to access the same data - all but the first locker of the contended data get blocked or thrown out, which clearly hurts throughput since work is being done that will not result in a successful transaction flowing through the system.

However data in the database is not the only shared resource in a transaction system. I already talked about application servers being resource sharing mechanisms - any of these resources could be contended for, so the application server itself needs to lock in-memory data structures to avoid problems if they are accessed on behalf of multiple requests in parallel, and contention can result here too. Of course, layers other than the app. Server are resource sharing too - on a typical server, those 60 execute threads you configured for WebLogic are probably being executed across a handful of CPUs at the most - when contention for CPUs occurs, the unlucky threads must wait in line until a CPU is free and so on with memory, disk, etc.

Overall, everything I have thus far mentioned represents a massive headache - the development of the performance tests, the running of the tests while all the tuning is done, the allocation of server resources to meet the predicted demands, and all of this is repeated with changing application releases and server environment releases and the resulting sized systems then have to stand up to unpredictable real-life loading. Not only is this a headache, it is a major lifetime cost of every application.

The astute among you will have noticed that my e-mail address has changed; that's because I have joined Azul Systems, who have a unique solution to these issues. Java is highly multithreaded, so it provides systems that contain many CPUs, each with many cores so those Java threads really result in parallelization. Then it provides support for optimistic locking on synchronized Java objects, to reduce contention within the Java software layer, then it provides pools of memory that can be shared between multiple applications. In short, the Azul Appliance provides a Java execution engine that dwarfs your systems' capacity to consume resources by overwhelming your individual applications with CPU and memory resources in order to try and alleviate any bottlenecks caused by the shortage of either in the traditional VM environment.

This tactic has the additional benefit that it more or less removes the need to do tuning on a per-application basis, since the set of resources provided by the appliance is so big that it can be readily shared among multiple applications that previously each required headroom on their own servers for peaks in demand. This sharing is possible because on aggregate the demand peaks will be smoothed (since it is improbable that many unrelated applications will all hit a demand peak at once), so demand can be met from the pooled resources, which leaves you free not only from application-level sizing (and the associated costs), but also from large-scale overprovisioning of hardware on a per-application basis too. All this heralds a new era of cheaply procured and managed appliances to run highly performant Java applications. For more details, visit www.azulsystems.com. That's all for this month; watch out for a repeat performance next month.

More Stories By Peter Holditch

Peter Holditch is a senior presales engineer in the UK for Azul Systems. Prior to joining Azul he spent nine years at BEA systems, going from being one of their first Professional Services consultants in Europe and finishing up as a principal presales engineer. He has an R&D background (originally having worked on BEA's Tuxedo product) and his technical interests are in high-throughput transaction systems. "Of the pitch" Peter likes to brew beer, build furniture, and undertake other ludicrously ambitious projects - but (generally) not all at the same time!

Comments (3) View Comments

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Most Recent Comments
Peter Holditch 10/31/05 09:57:17 PM EST

Of course, no technology can change the laws of physics, so if all your threads are truly contending for one resource, they will have to be serialised.
However, if the threads are contending for a java lock AND it turns out that they would not actually corrupt data each other is looking at (i.e the java lock is very coarse grained, but the data accessed within it is fine grained) then the Azul appliance can help because its "Speculative Multiaddress Atomicity" feature allows optimistic locking to take place, as mentioned in the article.
(see 'Optimistic Thread Concurrency' here: http://www.azulsystems.com/products/cpools_tech.html )

WebLogic Journal New Desk 10/29/05 12:32:08 PM EDT

WebLogic Performance: Pursuit of Speed Isn't Everything. 'High performance' is what everybody strives for when putting together a new system. Technical folk often spend hours hung up on the raw speed of their code, and a certain machismo can be derived from shaving milliseconds off that pesky transaction that is the latest pride and joy. Often, this time is not very well spent.

queZZtion 10/29/05 11:55:45 AM EDT

||| on a typical server, those 60 execute threads you configured for WebLogic are probably being executed across a handful of CPUs at the most |||

What about when contention occcurs?

@ThingsExpo Stories
Widespread fragmentation is stalling the growth of the IIoT and making it difficult for partners to work together. The number of software platforms, apps, hardware and connectivity standards is creating paralysis among businesses that are afraid of being locked into a solution. EdgeX Foundry is unifying the community around a common IoT edge framework and an ecosystem of interoperable components.
"MobiDev is a software development company and we do complex, custom software development for everybody from entrepreneurs to large enterprises," explained Alan Winters, U.S. Head of Business Development at MobiDev, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
Large industrial manufacturing organizations are adopting the agile principles of cloud software companies. The industrial manufacturing development process has not scaled over time. Now that design CAD teams are geographically distributed, centralizing their work is key. With large multi-gigabyte projects, outdated tools have stifled industrial team agility, time-to-market milestones, and impacted P&L stakeholders.
"Space Monkey by Vivent Smart Home is a product that is a distributed cloud-based edge storage network. Vivent Smart Home, our parent company, is a smart home provider that places a lot of hard drives across homes in North America," explained JT Olds, Director of Engineering, and Brandon Crowfeather, Product Manager, at Vivint Smart Home, in this SYS-CON.tv interview at @ThingsExpo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
"Akvelon is a software development company and we also provide consultancy services to folks who are looking to scale or accelerate their engineering roadmaps," explained Jeremiah Mothersell, Marketing Manager at Akvelon, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
In his session at 21st Cloud Expo, Carl J. Levine, Senior Technical Evangelist for NS1, will objectively discuss how DNS is used to solve Digital Transformation challenges in large SaaS applications, CDNs, AdTech platforms, and other demanding use cases. Carl J. Levine is the Senior Technical Evangelist for NS1. A veteran of the Internet Infrastructure space, he has over a decade of experience with startups, networking protocols and Internet infrastructure, combined with the unique ability to it...
"IBM is really all in on blockchain. We take a look at sort of the history of blockchain ledger technologies. It started out with bitcoin, Ethereum, and IBM evaluated these particular blockchain technologies and found they were anonymous and permissionless and that many companies were looking for permissioned blockchain," stated René Bostic, Technical VP of the IBM Cloud Unit in North America, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Conventi...
Gemini is Yahoo’s native and search advertising platform. To ensure the quality of a complex distributed system that spans multiple products and components and across various desktop websites and mobile app and web experiences – both Yahoo owned and operated and third-party syndication (supply), with complex interaction with more than a billion users and numerous advertisers globally (demand) – it becomes imperative to automate a set of end-to-end tests 24x7 to detect bugs and regression. In th...
"Cloud Academy is an enterprise training platform for the cloud, specifically public clouds. We offer guided learning experiences on AWS, Azure, Google Cloud and all the surrounding methodologies and technologies that you need to know and your teams need to know in order to leverage the full benefits of the cloud," explained Alex Brower, VP of Marketing at Cloud Academy, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clar...
Coca-Cola’s Google powered digital signage system lays the groundwork for a more valuable connection between Coke and its customers. Digital signs pair software with high-resolution displays so that a message can be changed instantly based on what the operator wants to communicate or sell. In their Day 3 Keynote at 21st Cloud Expo, Greg Chambers, Global Group Director, Digital Innovation, Coca-Cola, and Vidya Nagarajan, a Senior Product Manager at Google, discussed how from store operations and ...
"There's plenty of bandwidth out there but it's never in the right place. So what Cedexis does is uses data to work out the best pathways to get data from the origin to the person who wants to get it," explained Simon Jones, Evangelist and Head of Marketing at Cedexis, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
SYS-CON Events announced today that CrowdReviews.com has been named “Media Sponsor” of SYS-CON's 22nd International Cloud Expo, which will take place on June 5–7, 2018, at the Javits Center in New York City, NY. CrowdReviews.com is a transparent online platform for determining which products and services are the best based on the opinion of the crowd. The crowd consists of Internet users that have experienced products and services first-hand and have an interest in letting other potential buye...
SYS-CON Events announced today that Telecom Reseller has been named “Media Sponsor” of SYS-CON's 22nd International Cloud Expo, which will take place on June 5-7, 2018, at the Javits Center in New York, NY. Telecom Reseller reports on Unified Communications, UCaaS, BPaaS for enterprise and SMBs. They report extensively on both customer premises based solutions such as IP-PBX as well as cloud based and hosted platforms.
It is of utmost importance for the future success of WebRTC to ensure that interoperability is operational between web browsers and any WebRTC-compliant client. To be guaranteed as operational and effective, interoperability must be tested extensively by establishing WebRTC data and media connections between different web browsers running on different devices and operating systems. In his session at WebRTC Summit at @ThingsExpo, Dr. Alex Gouaillard, CEO and Founder of CoSMo Software, presented ...
WebRTC is great technology to build your own communication tools. It will be even more exciting experience it with advanced devices, such as a 360 Camera, 360 microphone, and a depth sensor camera. In his session at @ThingsExpo, Masashi Ganeko, a manager at INFOCOM Corporation, introduced two experimental projects from his team and what they learned from them. "Shotoku Tamago" uses the robot audition software HARK to track speakers in 360 video of a remote party. "Virtual Teleport" uses a multip...
A strange thing is happening along the way to the Internet of Things, namely far too many devices to work with and manage. It has become clear that we'll need much higher efficiency user experiences that can allow us to more easily and scalably work with the thousands of devices that will soon be in each of our lives. Enter the conversational interface revolution, combining bots we can literally talk with, gesture to, and even direct with our thoughts, with embedded artificial intelligence, whic...
SYS-CON Events announced today that Evatronix will exhibit at SYS-CON's 21st International Cloud Expo®, which will take place on Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA. Evatronix SA offers comprehensive solutions in the design and implementation of electronic systems, in CAD / CAM deployment, and also is a designer and manufacturer of advanced 3D scanners for professional applications.
Leading companies, from the Global Fortune 500 to the smallest companies, are adopting hybrid cloud as the path to business advantage. Hybrid cloud depends on cloud services and on-premises infrastructure working in unison. Successful implementations require new levels of data mobility, enabled by an automated and seamless flow across on-premises and cloud resources. In his general session at 21st Cloud Expo, Greg Tevis, an IBM Storage Software Technical Strategist and Customer Solution Architec...
To get the most out of their data, successful companies are not focusing on queries and data lakes, they are actively integrating analytics into their operations with a data-first application development approach. Real-time adjustments to improve revenues, reduce costs, or mitigate risk rely on applications that minimize latency on a variety of data sources. In his session at @BigDataExpo, Jack Norris, Senior Vice President, Data and Applications at MapR Technologies, reviewed best practices to ...
An increasing number of companies are creating products that combine data with analytical capabilities. Running interactive queries on Big Data requires complex architectures to store and query data effectively, typically involving data streams, an choosing efficient file format/database and multiple independent systems that are tied together through custom-engineered pipelines. In his session at @BigDataExpo at @ThingsExpo, Tomer Levi, a senior software engineer at Intel’s Advanced Analytics gr...