Search Results

Search found 61986 results on 2480 pages for 'launch time'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 751/2480 | < Previous Page | 747 748 749 750 751 752 753 754 755 756 757 758  | Next Page >

  • ZFS for Database Log Files

    - by user12620111
    I've been troubled by drop outs in CPU usage in my application server, characterized by the CPUs suddenly going from close to 90% CPU busy to almost completely CPU idle for a few seconds. Here is an example of a drop out as shown by a snippet of vmstat data taken while the application server is under a heavy workload. # vmstat 1  kthr      memory            page            disk          faults      cpu  r b w   swap  free  re  mf pi po fr de sr s3 s4 s5 s6   in   sy   cs us sy id  1 0 0 130160176 116381952 0 16 0 0 0 0  0  0  0  0  0 207377 117715 203884 70 21 9  12 0 0 130160160 116381936 0 25 0 0 0 0 0  0  0  0  0 200413 117162 197250 70 20 9  11 0 0 130160176 116381920 0 16 0 0 0 0 0  0  1  0  0 203150 119365 200249 72 21 7  8 0 0 130160176 116377808 0 19 0 0 0 0  0  0  0  0  0 169826 96144 165194 56 17 27  0 0 0 130160176 116377800 0 16 0 0 0 0  0  0  0  0  1 10245 9376 9164 2  1 97  0 0 0 130160176 116377792 0 16 0 0 0 0  0  0  0  0  2 15742 12401 14784 4 1 95  0 0 0 130160176 116377776 2 16 0 0 0 0  0  0  1  0  0 19972 17703 19612 6 2 92  14 0 0 130160176 116377696 0 16 0 0 0 0 0  0  0  0  0 202794 116793 199807 71 21 8  9 0 0 130160160 116373584 0 30 0 0 0 0  0  0 18  0  0 203123 117857 198825 69 20 11 This behavior occurred consistently while the application server was processing synthetic transactions: HTTP requests from JMeter running on an external machine. I explored many theories trying to explain the drop outs, including: Unexpected JMeter behavior Network contention Java Garbage Collection Application Server thread pool problems Connection pool problems Database transaction processing Database I/O contention Graphing the CPU %idle led to a breakthrough: Several of the drop outs were 30 seconds apart. With that insight, I went digging through the data again and looking for other outliers that were 30 seconds apart. In the database server statistics, I found spikes in the iostat "asvc_t" (average response time of disk transactions, in milliseconds) for the disk drive that was being used for the database log files. Here is an example:                     extended device statistics     r/s    w/s   kr/s   kw/s wait actv wsvc_t asvc_t  %w  %b device     0.0 2053.6    0.0 8234.3  0.0  0.2    0.0    0.1   0  24 c3t60080E5...F4F6d0s0     0.0 2162.2    0.0 8652.8  0.0  0.3    0.0    0.1   0  28 c3t60080E5...F4F6d0s0     0.0 1102.5    0.0 10012.8  0.0  4.5    0.0    4.1   0  69 c3t60080E5...F4F6d0s0     0.0   74.0    0.0 7920.6  0.0 10.0    0.0  135.1   0 100 c3t60080E5...F4F6d0s0     0.0  568.7    0.0 6674.0  0.0  6.4    0.0   11.2   0  90 c3t60080E5...F4F6d0s0     0.0 1358.0    0.0 5456.0  0.0  0.6    0.0    0.4   0  55 c3t60080E5...F4F6d0s0     0.0 1314.3    0.0 5285.2  0.0  0.7    0.0    0.5   0  70 c3t60080E5...F4F6d0s0 Here is a little more information about my database configuration: The database and application server were running on two different SPARC servers. Storage for the database was on a storage array connected via 8 gigabit Fibre Channel Data storage and log file were on different physical disk drives Reliable low latency I/O is provided by battery backed NVRAM Highly available: Two Fibre Channel links accessed via MPxIO Two Mirrored cache controllers The log file physical disks were mirrored in the storage device Database log files on a ZFS Filesystem with cutting-edge technologies, such as copy-on-write and end-to-end checksumming Why would I be getting service time spikes in my high-end storage? First, I wanted to verify that the database log disk service time spikes aligned with the application server CPU drop outs, and they did: At first, I guessed that the disk service time spikes might be related to flushing the write through cache on the storage device, but I was unable to validate that theory. After searching the WWW for a while, I decided to try using a separate log device: # zpool add ZFS-db-41 log c3t60080E500017D55C000015C150A9F8A7d0 The ZFS log device is configured in a similar manner as described above: two physical disks mirrored in the storage array. This change to the database storage configuration eliminated the application server CPU drop outs: Here is the zpool configuration: # zpool status ZFS-db-41   pool: ZFS-db-41  state: ONLINE  scan: none requested config:         NAME                                     STATE         ZFS-db-41                                ONLINE           c3t60080E5...F4F6d0  ONLINE         logs           c3t60080E5...F8A7d0  ONLINE Now, the I/O spikes look like this:                     extended device statistics                  r/s    w/s   kr/s   kw/s wait actv wsvc_t asvc_t  %w  %b device     0.0 1053.5    0.0 4234.1  0.0  0.8    0.0    0.7   0  75 c3t60080E5...F8A7d0s0                     extended device statistics                  r/s    w/s   kr/s   kw/s wait actv wsvc_t asvc_t  %w  %b device     0.0 1131.8    0.0 4555.3  0.0  0.8    0.0    0.7   0  76 c3t60080E5...F8A7d0s0                     extended device statistics                  r/s    w/s   kr/s   kw/s wait actv wsvc_t asvc_t  %w  %b device     0.0 1167.6    0.0 4682.2  0.0  0.7    0.0    0.6   0  74 c3t60080E5...F8A7d0s0     0.0  162.2    0.0 19153.9  0.0  0.7    0.0    4.2   0  12 c3t60080E5...F4F6d0s0                     extended device statistics                  r/s    w/s   kr/s   kw/s wait actv wsvc_t asvc_t  %w  %b device     0.0 1247.2    0.0 4992.6  0.0  0.7    0.0    0.6   0  71 c3t60080E5...F8A7d0s0     0.0   41.0    0.0   70.0  0.0  0.1    0.0    1.6   0   2 c3t60080E5...F4F6d0s0                     extended device statistics                  r/s    w/s   kr/s   kw/s wait actv wsvc_t asvc_t  %w  %b device     0.0 1241.3    0.0 4989.3  0.0  0.8    0.0    0.6   0  75 c3t60080E5...F8A7d0s0                     extended device statistics                  r/s    w/s   kr/s   kw/s wait actv wsvc_t asvc_t  %w  %b device     0.0 1193.2    0.0 4772.9  0.0  0.7    0.0    0.6   0  71 c3t60080E5...F8A7d0s0 We can see the steady flow of 4k writes to the ZIL device from O_SYNC database log file writes. The spikes are from flushing the transaction group. Like almost all problems that I run into, once I thoroughly understand the problem, I find that other people have documented similar experiences. Thanks to all of you who have documented alternative approaches. Saved for another day: now that the problem is obvious, I should try "zfs:zfs_immediate_write_sz" as recommended in the ZFS Evil Tuning Guide. References: The ZFS Intent Log Solaris ZFS, Synchronous Writes and the ZIL Explained ZFS Evil Tuning Guide: Cache Flushes ZFS Evil Tuning Guide: Tuning ZFS for Database Performance

    Read the article

  • Does anyone know any good resources for learning how to market a web app?

    - by Jack Kinsella
    I'm a developer first and foremost. I write web apps but have a hard time generating traffic and converting potential users once I've released my product into the wild. I know I need to learn more about marketing but I don't know where to start as I've no baseline to judge the quality of the materials I stumble across. Does anyone know any websites, blogs, e-books or other resources for learning how to market effectively?

    Read the article

  • Make pygame's frame rate faster

    - by Smashery
    By profiling my game, I see that the vast majority of the execution time of my hobby game is between the blit and the flip calls. Currently, it's only running at around 13fps. My video card is fairly decent, so my guess is that pygame is not using it. Does anyone know of any graphics/display options I need to set in pygame to make this faster? Or is this just something that I have to live with since I've chosen pygame?

    Read the article

  • Schema Based Code Completion for NetBeans Platform Applications

    - by Geertjan
    Toni's recent blog entry provides, among several other interesting things, instructions for something I've been wanting to cover for a long time, which is schema based code completion: The above is a sample I created via Toni's tutorial, using the schema described here: http://www.w3schools.com/schema/schema_example.asp The support for the Navigator ain't bad either, especially considering I didn't do any coding at all to get all this: And here's where you can find the whole sample: http://java.net/projects/nb-api-samples/sources/api-samples/show/versions/7.2/misc/ShipOrder

    Read the article

  • Web Site Search Engines - Sending Your Site to Search Engine Sites

    Search engines are number one cost effective approach to market your business and web site. Studies indicate that vast majority viewers find web sites via leading search engines and directories. Quality listing on leading search engine or directory may drive targeted traffic to your website and improve your business in a short period of time.

    Read the article

  • Finding an SEO Service Provider to Work With

    SEO Companies are dime a dozen. With so many SEO companies out there, there should not be any issue finding someone to work with. However, if you are looking to get an SEO company that is reasonably price but at the same time is skilled, you may have to look hard.

    Read the article

  • What Is Spyware And How Does It Affect Your Computer

    Spyware is a type of malware (i.e., malicious software) that is installed on computers without the user';s consent. Spyware goes about collecting small amounts of information at a time about you. What... [Author: Daniel T. Driver - Computers and Internet - May 08, 2010]

    Read the article

  • Google I/O 2012 - Protecting your User Experience While Integrating 3rd-party Code

    Google I/O 2012 - Protecting your User Experience While Integrating 3rd-party Code Patrick Meenan The amount of 3rd-party content included on websites is exploding (social sharing buttons, user tracking, advertising, code libraries, etc). Learn tips and techniques for how best to integrate them into your sites without risking a slower user experience or even your sites becoming unavailable. For all I/O 2012 sessions, go to developers.google.com From: GoogleDevelopers Views: 598 12 ratings Time: 48:04 More in Science & Technology

    Read the article

  • Geo for Good Summit Highlights

    Geo for Good Summit Highlights The last week of September, Google hosted the Geo for Good User Summit, for nonprofit mapping and technology specialists to update the nonprofit community about new and special features of Google's mapping products. In this week's Maps Developers Live event, Mano Marks from Maps Developer Relations and Raleigh Seamster, Program Manager with the Google Earth Outreach team will talk about the highlights of the Summit and show off some great examples of people using Maps to help the world. From: GoogleDevelopers Views: 0 0 ratings Time: 00:00 More in Education

    Read the article

  • VCPASS: Extend your T-SQL Scripting with PowerShell

    - by dbaduck
    Date: November 16, 2011 Extend your T-SQL Scripting with PowerShell Description: I'll be covering some of the different way we can use PowerShell to extend our T-SQL scripting. This session will include a mix of using SMO, .NET classes, and SQLPS to help you understand the power for new scripting technology. At the end we’ll be creating a solution that put together all this techniques. Date/Time: 11/16/2011 1:00 PM - 2:00 PM EST Registration Link: https://www.livemeeting.com/lrs/8000181573/Registration.aspx?pageName=7wzjxg98v9160twm...(read more)

    Read the article

  • Oracle University New Courses (Week 14)

    - by swalker
    Oracle University released the following new (versions of) courses recently: Database Oracle Data Modeling and Relational Database Design (4 days) Fusion Middleware Oracle Directory Services 11g: Administration (5 days) Oracle Unified Directory 11g: Services Deployment Essentials (2 days) Oracle GoldenGate 11g Management Pack: Overview (1 day) Business Intelligence & Datawarehousing Oracle Database 11g: Data Mining Techniques (2 days) Oracle Solaris Oracle Solaris 10 System Administration for HP-UX Administrators (5 days) E-Business Suite R12.x Oracle Time and Labor Fundamentals Get in contact with your local Oracle University team for more details and course dates. Stay Connected to Oracle University: LinkedIn OracleMix Twitter Facebook Google+

    Read the article

  • How to handle encryption key conflicts when synchronizing data?

    - by Rafael
    Assume that there is data that gets synchronized between several devices. The data is protected with a symmetric encryption algorithm and a key. The key is stored on each device and encrypted with a password. When a user changes the password only the key gets re-encrypted. Under normal circumstances, when there is a good network connection to other peers, the current key gets synchronized and all data on the new device gets encrypted with the same key. But how to handle situations where a new device doesn’t have a network connection and e.g. creates its own new, but incompatible key? How to keep the usability as high as possible under such circumstances? The application could detect that there is no network and hence refuse to start. That’s very bad usability in my opinion, because the application isn’t functional at all in this case. I don’t consider this a solution. The application could ignore the missing network connection and create a new key. But what to do when the application gains a network connection? There will be several incompatible keys and some parts of the underlying data could only be encrypted with one key and other parts with another key. The situation would get worse if there would be more keys than just two and the application would’ve to ask every time for a password when another object that should get decrypted with another key would be needed. It is very messy and time consuming to try to re-encrypt all data that is encrypted with another key with a main key. What should be the main key at all in this case? The oldest key? The key with the most encrypted objects? What if the key got synchronized but not all objects that got encrypted with this particular key? How should the user know for which particular password the application asks and why it takes probably very long to re-encrypt the data? It’s very hard to describe encryption “issues” to users. So far I didn’t find an acceptable solution, nor some kind of generic strategy. Do you have some hints about a concrete strategy or some books / papers that describe synchronization of symmetrically encrypted data with keys that could cause conflicts?

    Read the article

  • Google I/O 2010 - A JIT Compiler for Android's Dalvik VM

    Google I/O 2010 - A JIT Compiler for Android's Dalvik VM Google I/O 2010 - A JIT Compiler for Android's Dalvik VM Android 301 Ben Cheng, Bill Buzbee In this session we will outline the design of a JIT Compiler suitable for embedded Android devices. Topics will include an architectural overview, the rationale for design decisions and the special support for JIT verification, testing and tuning. For all I/O 2010 sessions, please go to code.google.com From: GoogleDevelopers Views: 3 0 ratings Time: 01:00:14 More in Science & Technology

    Read the article

  • Partner Up for FY13: LIVE Oracle PartnerNetwork Kickoff is June 26-27

    - by oracletechnet
    Work for an Oracle partner? Then this is appointment viewing: On June 26-27, in different time zones worldwide, Oracle PartnerNetwork is live-streaming its FY13 Partner Kickoff. SVP Alliance & Channels Judson Althoff will join other technical executives, including Thomas Kurian (EVP Software Development) and John Fowler (EVP Hardware & Systems), to discuss the full range of business opportunities now available to Oracle partners. Register for your regional Webcast today. 

    Read the article

  • 7 Things About Online Marketing I Learned Playing World of Warcraft

    Are you a World of Warcraft addict too? Did you always get told off by others that you get nothing from WoW to apply to the real world? Well tell them to think again. It is highly comparable to Online Marketing, from starting off as a Newbie, Competing, Gaining Comrades, Leveling up, Investing Time, Earning Gold, and Not being left behind. Read up on the 7 Things about Online Marketing I learned playing World of Warcraft!

    Read the article

  • Why is multithreading often preferred for improving performance?

    - by user1849534
    I have a question, it's about why programmers seems to love concurrency and multi-threaded programs in general. I'm considering 2 main approaches here: an async approach basically based on signals, or just an async approach as called by many papers and languages like the new C# 5.0 for example, and a "companion thread" that manages the policy of your pipeline a concurrent approach or multi-threading approach I will just say that I'm thinking about the hardware here and the worst case scenario, and I have tested this 2 paradigms myself, the async paradigm is a winner at the point that I don't get why people 90% of the time talk about multi-threading when they want to speed up things or make a good use of their resources. I have tested multi-threaded programs and async program on an old machine with an Intel quad-core that doesn't offer a memory controller inside the CPU, the memory is managed entirely by the motherboard, well in this case performances are horrible with a multi-threaded application, even a relatively low number of threads like 3-4-5 can be a problem, the application is unresponsive and is just slow and unpleasant. A good async approach is, on the other hand, probably not faster but it's not worst either, my application just waits for the result and doesn't hangs, it's responsive and there is a much better scaling going on. I have also discovered that a context change in the threading world it's not that cheap in real world scenario, it's in fact quite expensive especially when you have more than 2 threads that need to cycle and swap among each other to be computed. On modern CPUs the situation it's not really that different, the memory controller it's integrated but my point is that an x86 CPUs is basically a serial machine and the memory controller works the same way as with the old machine with an external memory controller on the motherboard. The context switch is still a relevant cost in my application and the fact that the memory controller it's integrated or that the newer CPU have more than 2 core it's not bargain for me. For what i have experienced the concurrent approach is good in theory but not that good in practice, with the memory model imposed by the hardware, it's hard to make a good use of this paradigm, also it introduces a lot of issues ranging from the use of my data structures to the join of multiple threads. Also both paradigms do not offer any security abut when the task or the job will be done in a certain point in time, making them really similar from a functional point of view. According to the X86 memory model, why the majority of people suggest to use concurrency with C++ and not just an async approach ? Also why not considering the worst case scenario of a computer where the context switch is probably more expensive than the computation itself ?

    Read the article

  • Common SOA Problems by C2B2

    - by JuergenKress
    SOA stands for Service Oriented Architecture and has only really come together as a concrete approach in the last 15 years or so, although the concepts involved have been around for longer. Oracle SOA Suite is based around the Service Component Architecture (SCA) devised by the Open SOA collaboration of companies including Oracle and IBM. SCA, as used in SOA suite, is designed as a way to crystallise the concepts of SOA into a standard which ensures that SOA principles like the separation of application and business logic are maintained. Orchestration or Integration? A common thing to see with many people who are beginning to either build a new SOA based infrastructure, or move an old system to be service oriented, is confusion in the purpose of SOA technologies like BPEL and enterprise service buses. For a lot of problems, orchestration tools like BPEL or integration tools like an ESB will both do the job and achieve the right objectives; however it’s important to remember that, although a hammer can be used to drive a screw into wood, that doesn’t mean it’s the best way to do it. Service Integration is the act of connecting components together at a low level, which usually results in a single external endpoint for you to expose to your customers or other teams within your organisation – a simple product ordering system, for example, might integrate a stock checking service and a payment processing service. Process Orchestration, however, is generally a higher level approach whereby the (often externally exposed) service endpoints are brought together to track an end-to-end business process. This might include the earlier example of a product ordering service and couple it with a business rules service and human task to handle edge-cases. A good (but not exhaustive) rule-of-thumb is that integrations performed by an ESB will usually be real-time, whereas process orchestration in a SOA composite might comprise processes which take a certain amount of time to complete, or have to wait pending manual intervention. BPEL vs BPMN For some, with pre-existing SOA or business process projects, this decision is effectively already made. For those embarking on new projects it’s certainly an important consideration for those using Oracle SOA software since, due to the components included in SOA Suite and BPM Suite, the choice of which to buy is determined by what they offer. Oracle SOA suite has no BPMN engine, whereas BPM suite has both a BPMN and a BPEL engine. SOA suite has the ESB component “Mediator”, whereas BPM suite has none. Decisions must be made, therefore, on whether just one or both process modelling languages are to be used. The wrong decision could be costly further down the line. Design for performance: Read the complete article here. SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Facebook Wiki Technorati Tags: C2B2,SOA best practice,SOA Community,Oracle SOA,Oracle BPM,Community,OPN,Jürgen Kress

    Read the article

  • OK, How Does SEO Work?

    SEO, which is short for Search Engine Optimisation, works by making your site "friendlier" for search engines such as Google to list in their index. No-one knows for sure just how many pages Google has indexed. It gave up posting that figure some time ago as it's irrelevant to the average internet surfer - we only want relevant results when we're searching and don't really care about the literally millions of pages that were discarded on the way.

    Read the article

  • From the Tips Box: iPhone Sleep Monitors, Testing IR Remotes with a Camera, and Glowing Easter Eggs Redux

    - by Jason Fitzpatrick
    Once a week we round up some great reader tips and share them with everyone. This week we’re looking at using your iPhone as a sleep monitor that wakes you at an optimum time, how to test your remote with a digital camera, and a clever way to craft glowing Easter eggs. How to Own Your Own Website (Even If You Can’t Build One) Pt 3 How to Sync Your Media Across Your Entire House with XBMC How to Own Your Own Website (Even If You Can’t Build One) Pt 2

    Read the article

  • Domain Renewal Explained

    Did you know that you never really ?own? a domain name perpetually? Well, it?s true. What you do is rent the ownership of a domain name for a fixed period of time ranging from 1 year to 10 years. Onc... [Author: Tanya Smith - Computers and Internet - April 03, 2010]

    Read the article

  • How to find out if my hosting's speed is good enough?

    - by Mert Nuhoglu
    There are lots of different online performance tests: Google PageSpeed Insights iWebTool Speed Test AlertFox Page Load Time WebPageTest Also there are several desktop/client software such as: ping tool YSlow Firebug's Net console Fiddler Http Watch I just want to decide if my hosting provider has a good enough performance or if I need to switch my hosting to another provider. So, which tool should I use to compare my hosting provider with other hosting providers?

    Read the article

  • Vermont IT Jobs: Local ASP.NET Contractor possible hire

    The website www.imsuperb.com is looking for an ASP.NET developer to help them out with a site update. This is a contract position that could lead to a full time job. Contact Nick Lynch at [email protected] you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

    Read the article

  • VS 2010 snippet manager and quickCode

    - by Michael Freidgeim
    During the last few years I've used QuickCode and it was very helpful. VS 2010 has  Code Snippets Manager that MS finally made quite convenient to use, so I will use it in a future.   I will need to convert my QuickCode commands to VS snippets. I am sure I will miss Alt-Q hotkey for some time.

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 747 748 749 750 751 752 753 754 755 756 757 758  | Next Page >