Search Results

Search found 16547 results on 662 pages for 'physical design'.

Page 267/662 | < Previous Page | 263 264 265 266 267 268 269 270 271 272 273 274  | Next Page >

  • High I/O latency with software RAID, LUKS encrypted and LVM partitioned KVM setup

    - by aef
    I found out a performance problems with a Mumble server, which I described in a previous question are caused by an I/O latency problem of unknown origin. As I have no idea what is causing this and how to further debug it, I'm asking for your ideas on the topic. I'm running a Hetzner EX4S root server as KVM hypervisor. The server is running Debian Wheezy Beta 4 and KVM virtualisation is utilized through LibVirt. The server has two different 3TB hard drives as one of the hard drives was replaced after S.M.A.R.T. errors were reported. The first hard disk is a Seagate Barracuda XT ST33000651AS (512 bytes logical, 4096 bytes physical sector size), the other one a Seagate Barracuda 7200.14 (AF) ST3000DM001-9YN166 (512 bytes logical and physical sector size). There are two Linux software RAID1 devices. One for the unencrypted boot partition and one as container for the encrypted rest, using both hard drives. Inside the latter RAID device lies an AES encrypted LUKS container. Inside the LUKS container there is a LVM physical volume. The hypervisor's VFS is split on three logical volumes on the described LVM physical volume: one for /, one for /home and one for swap. Here is a diagram of the block device configuration stack: sda (Physical HDD) - md0 (RAID1) - md1 (RAID1) sdb (Physical HDD) - md0 (RAID1) - md1 (RAID1) md0 (Boot RAID) - ext4 (/boot) md1 (Data RAID) - LUKS container - LVM Physical volume - LVM volume hypervisor-root - LVM volume hypervisor-home - LVM volume hypervisor-swap - … (Virtual machine volumes) The guest systems (virtual machines) are mostly running Debian Wheezy Beta 4 too. We have one additional Ubuntu Precise instance. They get their block devices from the LVM physical volume, too. The volumes are accessed through Virtio drivers in native writethrough mode. The IO scheduler (elevator) on both the hypervisor and the guest system is set to deadline instead of the default cfs as that happened to be the most performant setup according to our bonnie++ test series. The I/O latency problem is experienced not only inside the guest systems but is also affecting services running on the hypervisor system itself. The setup seems complex, but I'm sure that not the basic structure causes the latency problems, as my previous server ran four years with almost the same basic setup, without any of the performance problems. On the old setup the following things were different: Debian Lenny was the OS for both hypervisor and almost all guests Xen software virtualisation (therefore no Virtio, also) no LibVirt management Different hard drives, each 1.5TB in size (one of them was a Seagate Barracuda 7200.11 ST31500341AS, the other one I can't tell anymore) We had no IPv6 connectivity Neither in the hypervisor nor in guests we had noticable I/O latency problems According the the datasheets, the current hard drives and the one of the old machine have an average latency of 4.12ms.

    Read the article

  • Database design for a media server containing movies, music, tv and everything in between?

    - by user364114
    In the near future I am attempting to design a media server as a personal project. MY first consideration to get the project underway is architecture, it will certainly be web based but more specifically than that I am looking for suggestions on the database design. So far I am considering something like the following, where I am using [] to represent a table, the first text is the table name to give an idea of purpose and the items within {} would be fields of the table. Also not, fid is functional id referencing some other table. [Item {id, value/name, description, link, type}] - this could be any entity, single song or whole music album, game, movie - almost see this as a recursive relation, ie. a song is an item but an album that song is part of is also an item or for example a tv season is an item, with multiple items being tv episodes [Type {id, fid, mime type, etc}] - file type specific information - could identify how code handles streaming/sending this item to a user [Location {id, fid, path to file?}] [Users {id, username, email, password, ...? }] - user account information [UAC {id, fid, acess level}] - i almost feel its more flexible to seperate access control permissions form the user accounts themselves [ItemLog {id, fid, fid2, timestamp}] - fid for user id, and fid2 for item id - this way we know what user access what when [UserLog {id, fid, timestamp}] -both are logs for access, whether login or last item access [Quota {id, fid, cap}] - some sort of way to throttle users from queing up the entire site and letting it download ... Suggestions or comments are welcome as the hope is that this project will be a open source project once some code is laid out.

    Read the article

  • Canonical resource for forms-based design in ASP.NET MVC?

    - by Robert Harvey
    Is there a resource on the web that describes various form scenarios in ASP.NET MVC, and gives example solutions within a sensible, consistent design philosophy? Examples of such scenarios might be: One-to-many forms, like invoice data-entry forms. Foreign-table forms such as Add New User in a form that requires specifying a user Forms that require dynamic interaction, using Ajax or JSON. Popup forms Forms requiring multiple data records to be input, without postbacks. Note that there is considerable conceptual and technological overlap among these example scenarios. I am aware that there is a vast patchwork quilt of available technologies and examples out there that provide partial solutions and pieces of solutions, such as jQuery Ajax, CSS, and so forth. But I would like guidance in using these technologies in more effective and consistent ways. I am not considering web forms integration with an ASP.NET MVC application; I would still like my applications to be pure MVC. Nor am I, at the moment, considering a paid solution like Telerik. But I would like to know if someone has already done some of the work combining these technologies into a consistent, cohesive whole, that follows a sensible design philosophy. (an open source framework, perhaps?)

    Read the article

  • How to design data storage for partitioned tagging system?

    - by Morgan Cheng
    How to design data storage for huge tagging system (like digg or delicious)? There is already discussion about it, but it is about centralized database. Since the data is supposed to grow, we'll need to partition the data into multiple shards soon or later. So, the question turns to be: How to design data storage for partitioned tagging system? The tagging system basically has 3 tables: Item (item_id, item_content) Tag (tag_id, tag_title) TagMapping(map_id, tag_id, item_id) That works fine for finding all items for given tag and finding all tags for given item, if the table is stored in one database instance. If we need to partition the data into multiple database instances, it is not that easy. For table Item, we can partition its content with its key item_id. For table Tag, we can partition its content with its key tag_id. For example, we want to partition table Tag into K databases. We can simply choose number (tag_id % K) database to store given tag. But, how to partition table TagMapping? The TagMapping table represents the many-to-many relationship. I can only image to have duplication. That is, same content of TagMappping has two copies. One is partitioned with tag_id and the other is partitioned with item_id. In scenario to find tags for given item, we use partition with tag_id. If scenario to find items for given tag, we use partition with item_id. As a result, there is data redundancy. And, the application level should keep the consistency of all tables. It looks hard. Is there any better solution to solve this many-to-many partition problem?

    Read the article

  • What are the best software/website UI design you have even seen?

    - by Edwin
    What are the best UI design in terms of usability and esthetics you have even seen? I mean both desktop software (of all OS) and website. My list: Picasa 3 - the way it organizes photos. Find-and-highlight-as-you-type in google Chrome. Dynamic search hints when entering something in the search box in Gmail. I'm not a Mac OS X user, but I have seen in most windows on the top toolbar there are both the icons and texts shown for each function, as apposed to on Windows I have seen many programs (MS Office included) have many small toolbar icons which you can hardly understand what they do until you hover the mouse on it for a while to see the hints (if any). The ability to search an setting in Eclipse IDE. the way to make 3D models in Google Sketchup. the way to label an email in Gmail. What are you list? Well, I couldn't resist to list some annoying UI design I have experienced and remember at this moment. IE on Windows server, when you visit the new website, you have to click many times to get it added to the white list before you can start browsing, IIRC, it's not fixed in IE 8 when that last time I used it on Windows 2008. The default search behavior in the File Explorer on Windows xp, that animated thing... the dialog that shows up when you are trying to save a plain text CSV file in Excel after applied some formatting options which does not compatible with CSV.

    Read the article

  • SQL Database Schema Design For Large 3 Billion Relationship Database.

    - by K-Bell
    Get your geek on. Can you solve this? I am designing a products database for SQL Server 2008 R2 Ed. (not Enterprise Ed.) that will be used to store custom product configurations for over 30,000 distinct products. The database will have up to 500 users at a time. Here is the design problem… Each Product has a collection of Parts (up to 50 parts per product). So if I have 30,000 Products and each of them can have up to 50 Parts, that’s 1.5 million distinct Product-to-Part relationships …or as an equation… 30,000 (Products) X 50 (Parts) = 1.5 million Product-to-Parts records. …and If… Each Part can have up to 2000 finish options (A finish is a paint color). NOTE: Only one finish will be selected by a user at run-time. The 2000 finish options I need to store are the allowed options for a specific part on a specific product. So if I have 1.5 million distinct product-to-part relationships/records and each of those parts can have up to 2,000 finishes that is 3 billion allowable product-to-part-to finish relationships/records …or as an equation… 1.5 million (Parts) x 2,000 (Finishes) = 3 Billion Product-to-Part-to-Finishes records. How can I design this database so that I can execute fast and efficient queries for a specific product and return its list of Parts and all the allowable Finishes for each part without 3 Billion Product-to-Part-to-Finish records? Read time is more important then write time. Please post your thoughts/suggestions if you have experience with large databases. Thanks!

    Read the article

  • Looking Back at MIX10

    - by WeigeltRo
    It’s the sad truth of my life that even though I’m fascinated by airplanes and flight in general since my childhood days, my body doesn’t like flying. Even the ridiculously short flights inside Germany are taking their toll on me each time. Now combine this with sitting in the cramped space of economy class for many hours on a transatlantic flight from Germany to Las Vegas and back, and factor in some heavy dose of jet lag (especially on my way eastwards), and you get an idea why after coming back home I had this question on my mind: Was it really worth it to attend MIX10? This of course is a question that will also be asked by my boss at Comma Soft (for other reasons, obviously), who decided to send me and my colleague Jens Schaller, to the MIX10 conference. (A note to my German readers: An dieser Stelle der Hinweis, dass Comma Soft noch Silverlight-Entwickler und/oder UI-Designer für den Standort Bonn sucht – aussagekräftige Bewerbungen bitte an [email protected]) Too keep things short: My answer is yes. Before I’ll go into detail, let me ask the heretical questions whether tech conferences in general still make sense. There was a time, where actually being at a tech conference gave you a head-start in regard to learning about new technologies. Nowadays this is no longer true, where every bit of information and every detail is immediately twittered, blogged and whatevered to death. In the case of MIX10 you even can download the video-taped sessions shortly after. So: Does visiting a conference still make sense? It depends on what you expect from a conference. It should be clear to everybody that you’ll neither get exclusive information, nor receive training in a small group. What a conference does offer that sitting in front of your computer does not can be summarized as follows: Focus Being away from work and home will help you to focus on the presented information. Of course there are always the poor guys who are haunted by their work (with mails and short text messages reporting the latest showstopper problem), but in general being out of your office makes a huge difference. Inspiration With the focus comes the emotional involvement. I find it much easier to absorb information if I feel that certain vibe when sitting in a session. This still means that I have put work into reviewing the information later, but it’s a better starting point. And all the impressions collected at a (good) conference combined lead to a higher motivation – be it by the buzz (“this is gonna be sooo cool!”) or by the fear to fall behind (“man, we’ll have work on this, or else…”). People At a conference it’s pretty easy to get into contact with other people during breakfast, lunch and other breaks. This is a good opportunity to get a feel for what other development teams are doing (on a very general level of course, nobody will tell you about their secret formula) and what they are thinking about specific technologies. So MIX10 did offer focus, inspiration and people, but that would have meant nothing without valuable content. When I (being a frontend developer with a strong interest in UI/UX) planned my visit to MIX10, I made the decision to focus on the "soft" topics of design, interaction and user experience. I figured that I would be bombarded with all the technical details about Silverlight 4 anyway in the weeks and months to come. Actually, I would have liked to catch a few technical sessions, but the agenda wasn’t exactly in favor of people interested in any kind of Silverlight and UI/UX/Design topics. That’s one of my few complaints about the conference – I would have liked one more day and/or more sessions per day. Overall, the quality of the workshops and sessions was pretty high. In fact, looking back at my collection of conferences I’ve visited in the past I’d say that MIX10 ranks somewhere near the top spot. Here’s an overview of the workshops/sessions I attended (I’ll leave out the keynotes): Day 0 (Workshops on Sunday) Design Fundamentals for Developers Robby Ingebretsen is the man! Great workshop in three parts with the perfect mix of examples, well-structured definition of terminology and the right dose of humor. Robby was part of the WPF team before founding his own company so he not only has a strong interest in design (and the skillz!) but also the technical background.   Design Tools and Techniques Originally announced to be held by Arturo Toledo, the Rosso brothers from ArcheType filled in for the first two parts, and Corrina Black had a pretty general part about the Windows Phone UI. The first two thirds were a mixed bag; the two guys definitely knew what they were talking about, and the demos were great, but the talk lacked the preparation and polish of a truly great presentation. Corrina was not allowed to go into too much detail before the keynote on Monday, but the session was still very interesting as it showed how much thought went into the Windows Phone UI (and there’s always a lot to learn when people talk about their thought process). Day 1 (Monday) Designing Rich Experiences for Data-Centric Applications I wonder whether there was ever a test-run for this session, but what Ken Azuma and Yoshihiro Saito delivered in the first 15 minutes of a 30-minutes-session made me walk out. A commercial for a product (just great: a video showing a SharePoint plug-in in an all-Japanese UI) combined with the most generic blah blah one could imagine. EPIC FAIL.   Great User Experiences: Seamlessly Blending Technology & Design I switched to this session from the one above but I guess I missed the interesting part – what I did catch was what looked like a “look at the cool stuff we did” without being helpful. Or maybe I was just in a bad mood after the other session.   The Art, Technology and Science of Reading This talk by Kevin Larson was very interesting, but was more a presentation of what Microsoft is doing in research (pretty impressive) and in the end lacked a bit the helpful advice one could have hoped for.   10 Ways to Attack a Design Problem and Come Out Winning Robby Ingebretsen again, and again a great mix of theory and practice. The clean and simple, yet effective, UI of the reader app resulted in a simultaneous “wow” of Jens and me. If you’d watch only one session video, this should be it. Microsoft has to bring Robby back next year! Day 2 (Tuesday) Touch in Public: Multi-touch Interaction Design for Kiosks & Architectural Experiences Very interesting session by Jason Brush, a great inspiration with many details to look out for in the examples. Exactly what I was hoping for – and then some!   Designing Bing: Heart and Science How hard can it be to design the UI for a search engine? An input field and a list of results, that should be it, right? Well, not so fast! The talk by Paul Ray showed the many iterations to finally get it right (up to the choice of a specific blue for the links). And yes, I want an eye-tracking device to play around with!   The Elephant in the Room When Nishant Kothary presented a long list of what his session was not about, I told to myself (not having the description text present) “Am I in the wrong talk? Should I leave?”. Boy, was I wrong. A great talk about human factors in the process of designing stuff.   An Hour with Bill Buxton Having seen Bill Buxton’s presentation in the keynote, I just had to see this man again – even though I didn’t know what to expect. Being more or less unplanned and intended to be more of a conversation, the session didn’t provide a wealth of immediately useful information. Nevertheless Bill Buxton was impressive with his huge knowledge of seemingly everything. But this could/should have been a session some when in the evening and not in parallel to at least two other interesting talks. Day 3 (Wednesday) Design the Ordinary, Like the Fixie This session by DL Byron and Kevin Tamura started really well and brought across the message to keep things simple. But towards the end the talk lost some of its steam. And, as a member of the audience pointed out, they kind of ignored their own advice when they used a fancy presentation software other then PowerPoint that sometimes got in the way of showing things.   Developing Natural User Interfaces Speaking of alternative presentation software, Joshua Blake definitely had the most remarkable alternative to PowerPoint, a self-written program called NaturalShow that was controlled using multi-touch on a touch screen. Not a PowerPoint-killer, but impressive nevertheless. The (excellent) talk itself was kind of eye-opening in regard to what “multi-touch support” on various platforms (WPF, Silverlight, Windows Phone) actually means.   Treat your Content Right The talk by Tiffani Jones Brown wasn’t even on my planned schedule, but somehow I ended up in that session – and it was great. And even for people who don’t necessarily have to write content for websites, some points made by Tiffani are valid in many places, notably wherever you put texts with more than a single word into your UI. Creating Effective Info Viz in Microsoft Silverlight The last session of MIX10 I attended was kind of disappointing. At first things were very promising, with Matthias Shapiro giving a brief but well-structured introduction to info graphics and interactive visualizations. Then the live-coding began and while the result was interesting, too much time was spend on wrestling to get the code working. Ending earlier than planned, the talk was a bit light on actual content, but at least it included a nice list of resources. Conclusion It could be felt all across MIX10, UIs will take a huge leap forward; in fact, there are enough examples that have already. People who both have the technical know-how and at least a basic understanding of design (“literacy” as Bill Buxton called it) are in high demand. The concept of the MIX conference and initiatives like design.toolbox shows that Microsoft understands very well that frontend developers have to acquire new knowledge besides knowing how to hack code and putting buttons on a form. There are extremely exciting times before us, with lots of opportunity for those who are eager to develop their skills, that is for sure.

    Read the article

  • What are some good seminar topics that can be used to improve designer&developer communication?

    - by tactoth
    Hello guys the thing I'll tell is what happens in the company I work for but I know it's more like a common issue in software companies. I'm development team leader in a internet service company that provides service that's very similar to dropbox. In our company we have mainly two divisions: the tech division and the designers division, both have their own reporting hierarchy. Designers focus on designing UI and prioritizing features, while developers focus on implement designers' ideas (more like being driven as our big boss has said). Then here comes our issue: the DEV team and DES team communicate very bad. DEV complain DES for these reasons: Too frequent changing of requirements Too complicated interaction (our DEV team has actually learned many HCI principles) Documents for design are incomplete, usually you just get 'design principles' and it's up to DEV to complete design details. When you find design defects, you ask DES team to resolve them, then DES team quickly change the principles and you gonna spend another several weeks because the change is so fundamental. While DES complain DEV for these reasons: Code architecture is not good enough to adapt to changing requirements (Obviously DES knows something about software development) Product design is about principles, not details. DEV fails to realize this. Communication should be quick and should be mainly oral. Trying to make most feature discussion in document for reference is too overloaded and doesn't make sense. As you can see, DEV and DES have different ideas on product design, and encourages very different practice. We have this difference because of the way we work. So our solution is that we should plan some seminars to make each part more aware of the way the other part work. Then my question is, what are some good topics for such seminars? Guessing some people may not think seminars can solve this problem, please also suggest your solution.

    Read the article

  • BUILD 2013 Sessions&ndash;Building Great Windows Phone UI in XAML

    - by Tim Murphy
    Originally posted on: http://geekswithblogs.net/tmurphy/archive/2013/06/27/build-2013-sessionsndashbuilding-great-windows-phone-ui-in-xaml.aspx Even the simplest of smart phone apps can be a challenge to give a compelling UI regardless of the platform.  Windows Phone and XAML are no exception.  That is what got my interest in this session by Shawn Oster.  He took a checklist type approach to the subject is good considering that is about the only way that many us get things done. Shawn started out giving us a set of bad design/good design examples.  They very effectively showed how good design gives a sense of professionalism to your app that could determine if your wonderful idea actually makes money is DOA. I won’t go over all his points since you will be able to get the session online, but a few of his checklist points included design from the beginning instead of as an afterthought, not being afraid to leave white space and making sure your application elegantly supports both landscape and portrait modes.  The many gems make this a must watch for any developers who struggle with visual design. del.icio.us Tags: BUILD 2013,Windows Phone,XAML,Design

    Read the article

  • Offloading (Some) EBS 12 Reporting to Active Data Guard Instances

    - by Steven Chan
    For most Oracle Database users, Oracle Active Data Guard allows users to:Create a physical standby database for business continuity and disaster recoveryOffload reporting from the production database to the read-only physical standby databaseE-Business Suite customers have been able to use Active Data Guard to create physical standby databases for their EBS environments since the feature was introduced with the 11g Database.  EBS sysadmins can use the generic Active Data Guard documentation to take advantage of the Active Data Guard standby database capabilities.  I am pleased to announce that it is now possible to offload a subset of some ReportWriter-based reports -- but not all -- from a production EBS environment to an Active Data Guard physical standby database.  But before I go into the details of this newly-certified configuration, it's necessary to understand some details about what happens whenever someone attempts to access the E-Business Suite.

    Read the article

  • Basic networking problem with Ubuntu 9.04 on Acer Extensa 5635Z laptop

    - by sapporo
    I just installed Ubuntu 9.04 on a brand new Acer Extensa 5635Z laptop, but ethernet networking does't work (wireless doesn't work either, but I'd be happy with ethernet for now). eth0 isn't listed in /etc/network/interfaces: $ cat /etc/network/interfaces auto lo iface lo inet loopback lshw does show the nic, but I can't make much sense out of the information: $ sudo lshw -class network -sanitize *-network DISABLED description: Wireless interface product: AR928X Wireless Network Adapter (PCI-Express) vendor: Atheros Communications Inc. physical id: 0 bus info: pci@0000:07:00.0 logical name: wmaster0 version: 01 serial: [REMOVED] width: 64 bits clock: 33MHz capabilities: pm msi pciexpress msix bus_master cap_list logical ethernet physical wireless configuration: broadcast=yes driver=ath9k latency=0 module=ath9k multicast=yes wireless=IEEE 802.11bgn *-network UNCLAIMED description: Ethernet controller product: Attansic Technology Corp. vendor: Attansic Technology Corp. physical id: 0 bus info: pci@0000:09:00.0 version: c0 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress vpd cap_list configuration: latency=0 *-network DISABLED description: Ethernet interface physical id: 1 logical name: pan0 serial: [REMOVED] capabilities: ethernet physical configuration: broadcast=yes driver=bridge driverversion=2.3 firmware=N/A link=yes multicast=yes Thanks for your help!

    Read the article

  • Receiving Event ID: 10107, Hyper-V -VMMS

    - by Stargaten
    We are using physical disk on two of Guest operating systems. Is this a know issue? Do we need to have DPM 2010? "One or more physical disks are attached to virtual machine 'Myserver'. Back up programs that use the Hyper-V VSS writer cannot back up volumes that are attached to virtual machines as physical disks. To avoid potential data loss, use another method to back up the data on the physical disks. If you restore the data on this virtual machine, make sure to check the data of the physical disk for integrity. (Virtual machine ID 8EF3C0CB-967D-4D67-B4D8-7B782C7AC07C)"

    Read the article

  • What parts of this book are outdated? "Design of the UNIX Operating System" by Maurice Bach, 1986

    - by blee
    I learned programming on the job via high-level languages. I'm trying to gain a better understanding of the lower-level workings of computing and picked up "Design of the UNIX Operating System" by Maurice Bach. What do I need to know in terms of which topics in this book may not be relevant to understanding Linux nuts and bolts? Is there a newer book or Linux-specific book that I should read instead? I really like the clarity of this particular book, though.

    Read the article

  • In MySQL, what is the most effective query design for joining large tables with many to many relatio

    - by lighthouse65
    In our application, we collect data on automotive engine performance -- basically source data on engine performance based on the engine type, the vehicle running it and the engine design. Currently, the basis for new row inserts is an engine on-off period; we monitor performance variables based on a change in engine state from active to inactive and vice versa. The related engineState table looks like this: +---------+-----------+---------------+---------------------+---------------------+-----------------+ | vehicle | engine | engine_state | state_start_time | state_end_time | engine_variable | +---------+-----------+---------------+---------------------+---------------------+-----------------+ | 080025 | E01 | active | 2008-01-24 16:19:15 | 2008-01-24 16:24:45 | 720 | | 080028 | E02 | inactive | 2008-01-24 16:19:25 | 2008-01-24 16:22:17 | 304 | +---------+-----------+---------------+---------------------+---------------------+-----------------+ For a specific analysis, we would like to analyze table content based on a row granularity of minutes, rather than the current basis of active / inactive engine state. For this, we are thinking of creating a simple productionMinute table with a row for each minute in the period we are analyzing and joining the productionMinute and engineEvent tables on the date-time columns in each table. So if our period of analysis is from 2009-12-01 to 2010-02-28, we would create a new table with 129,600 rows, one for each minute of each day for that three-month period. The first few rows of the productionMinute table: +---------------------+ | production_minute | +---------------------+ | 2009-12-01 00:00 | | 2009-12-01 00:01 | | 2009-12-01 00:02 | | 2009-12-01 00:03 | +---------------------+ The join between the tables would be engineState AS es LEFT JOIN productionMinute AS pm ON es.state_start_time <= pm.production_minute AND pm.production_minute <= es.event_end_time. This join, however, brings up multiple environmental issues: The engineState table has 5 million rows and the productionMinute table has 130,000 rows When an engineState row spans more than one minute (i.e. the difference between es.state_start_time and es.state_end_time is greater than one minute), as is the case in the example above, there are multiple productionMinute table rows that join to a single engineState table row When there is more than one engine in operation during any given minute, also as per the example above, multiple engineState table rows join to a single productionMinute row In testing our logic and using only a small table extract (one day rather than 3 months, for the productionMinute table) the query takes over an hour to generate. In researching this item in order to improve performance so that it would be feasible to query three months of data, our thoughts were to create a temporary table from the engineEvent one, eliminating any table data that is not critical for the analysis, and joining the temporary table to the productionMinute table. We are also planning on experimenting with different joins -- specifically an inner join -- to see if that would improve performance. What is the best query design for joining tables with the many:many relationship between the join predicates as outlined above? What is the best join type (left / right, inner)?

    Read the article

  • Rotating sql table

    - by Sathish
    my sql talble has the following structure F1 F2 F3 F4 F5 Group 1 2 3 4 Design 5 6 7 8 now i want to read this and return a query result as show below please help F1 Value Group 1 Group 2 Group 3 Group 4 Design 5 Design 6 Design 7 Design 8

    Read the article

  • External USB Drive

    - by ErocM
    I have a server that I hooked up an external USB drive. It was formatted in windows and has files on it already. I'm new to Ubuntu so please be patient... I have two questions: Will Ubuntu see the drive since it was formatted in windows? How do I mount this drive or rather, how do I know it's seen by Ubuntu? Thanks! I did fdisk -l and this is what I have but I don't see it. It's a 1tb drive: Disk /dev/sda: 320.1 GB, 320072933376 bytes 255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x0001eb47 Device Boot Start End Blocks Id System /dev/sda1 * 2048 499711 248832 83 Linux /dev/sda2 501758 625141759 312320001 5 Extended /dev/sda5 501760 625141759 312320000 8e Linux LVM Disk /dev/sdc: 160.0 GB, 160041885696 bytes 255 heads, 63 sectors/track, 19457 cylinders, total 312581808 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/sdc doesn't contain a valid partition table Disk /dev/sdb: 160.0 GB, 160041885696 bytes 255 heads, 63 sectors/track, 19457 cylinders, total 312581808 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/sdb doesn't contain a valid partition table Disk /dev/mapper/ubuntu-root: 316.6 GB, 316577677312 bytes 255 heads, 63 sectors/track, 38488 cylinders, total 618315776 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/mapper/ubuntu-root doesn't contain a valid partition table Disk /dev/mapper/ubuntu-swap_1: 3217 MB, 3217031168 bytes 255 heads, 63 sectors/track, 391 cylinders, total 6283264 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 this is an external USB hard drive not a thumb drive :)

    Read the article

  • I can't install Ubuntu on my Dell Inspiron 15R at all

    - by Kieran Rimmer
    I'm attempting to install Ubuntu 12.04LTS, 64 bit onto a Dell Inspiron 15R laptop. I've shrunk down one of the windows partitions and even used gparted to format the vacant space as ext4. However, the install disk simply does not present any options when it comes to the partitioning step. What I get is a non-responsive blank table As well as the above, I've changed the BIOS settings so that USB emulation is disabled (as per Can't install on Dell Inspiron 15R), and changed the SATA Operation setting to all three possible options. Anyway, the install CD will bring up the trial version of ubuntu, and if I open terminal and type sudo fdisk -l, I get this: Disk /dev/sda: 1000.2 GB, 1000204886016 bytes 255 heads, 63 sectors/track, 121601 cylinders, total 1953525168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0xb4fd9215 Device Boot Start End Blocks Id System /dev/sda1 63 80324 40131 de Dell Utility Partition 1 does not start on physical sector boundary. /dev/sda2 * 81920 29044735 14481408 7 HPFS/NTFS/exFAT /dev/sda3 29044736 1005142015 488048640 7 HPFS/NTFS/exFAT /dev/sda4 1005154920 1953520064 474182572+ 83 Linux Disk /dev/sdb: 32.0 GB, 32017047552 bytes 255 heads, 63 sectors/track, 3892 cylinders, total 62533296 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0xb4fd923d Device Boot Start End Blocks Id System /dev/sdb1 2048 16775167 8386560 84 OS/2 hidden C: drive If I type 'sudo parted -l', I get: Model: ATA WDC WD10JPVT-75A (scsi) Disk /dev/sda: 1000GB Sector size (logical/physical): 512B/4096B Partition Table: msdos Number Start End Size Type File system Flags 1 32.3kB 41.1MB 41.1MB primary fat16 diag 2 41.9MB 14.9GB 14.8GB primary ntfs boot 3 14.9GB 515GB 500GB primary ntfs 4 515GB 1000GB 486GB primary ext4 Model: ATA SAMSUNG SSD PM83 (scsi) Disk /dev/sdb: 32.0GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 1049kB 8589MB 8588MB primary Warning: Unable to open /dev/sr0 read-write (Read-only file system). /dev/sr0 has been opened read-only. Error: Can't have a partition outside the disk! I've also tried a Kubuntu 12.04 and Linuxmint install disks, wityh the same problem. I'm completely lost here. Cheers, Kieran

    Read the article

  • Can't connect to WIFI after sleep Ubuntu 14.04

    - by user3380404
    After an upgrade over a previous version to Ubuntu 14.04 I have problems with connecting to WiFi. After suspending it won't reconnect to any existing network unless I restart the laptop. sudo lshw -C network: *-network description: Ethernet interface product: 82567LM Gigabit Network Connection vendor: Intel Corporation physical id: 19 bus info: pci@0000:00:19.0 logical name: eth0 version: 03 serial: 00:27:13:b4:d3:58 capacity: 1Gbit/s width: 32 bits clock: 33MHz capabilities: pm msi bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=e1000e driverversion=2.3.2-k firmware=1.8-3 latency=0 link=no multicast=yes port=twisted pair resources: irq:45 memory:fc200000-fc21ffff memory:fc225000-fc225fff ioport:1840(size=32) *-network description: Wireless interface product: PRO/Wireless 5100 AGN [Shiloh] Network Connection vendor: Intel Corporation physical id: 0 bus info: pci@0000:03:00.0 logical name: wlan0 version: 00 serial: 00:26:c6:c6:6b:c8 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless configuration: broadcast=yes driver=iwlwifi driverversion=3.13.0-29-generic firmware=8.83.5.1 build 33692 ip=10.0.1.160 latency=0 link=yes multicast=yes wireless=IEEE 802.11abgn resources: irq:48 memory:f4200000-f4201fff

    Read the article

  • What is(are) currently the best language(s) for modern web site design? Recommendations?

    - by Jereme Hall
    I'm a little out of date, before HTML4 and javascript got AJAXy. Does anyone have opinions about the best tools for web site design? I'd rather avoid ASP and .NET, since I've got a limited budget. This seems like a good time to start fresh. Please keep the replies on the coding recommendations, as I already know how to register a domain name, redirect it, set up Apache. (I could use some opinions on the various Apache flavors)

    Read the article

  • Does Python/Scipy have a firls( ) replacement (i.e. a weighted, least squares, FIR filter design)?

    - by delicasso
    I am porting code from Matlab to Python and am having trouble finding a replacement for the firls( ) routine. It is used for, least-squares linear-phase Finite Impulse Response (FIR) filter design. I looked at scipy.signal and nothing there looked like it would do the trick. Of course I was able to replace my remez and freqz algorithsm, so that's good. On one blog I found an algorithm that implemented this filter without weighting, but I need one with weights. Thanks, David

    Read the article

  • How do I turn off a custom IValueConverter at design time?

    - by Jonathan Allen
    How do I turn off a custom IValueConverter at design time? Basically I want to write this: Public Class MethodBinder Implements IValueConverter Public Function Convert(ByVal value As Object, ByVal targetType As System.Type, ByVal parameter As Object, ByVal culture As CultureInfo) As Object Implements IValueConverter.Convert If [DESIGN_TIME] Then Return Nothing If value IsNot Nothing Then Return CallByName(value, CStr(parameter), CallType.Method) Return Nothing End Function Public Function ConvertBack(ByVal value As Object, ByVal targetType As System.Type, ByVal parameter As Object, ByVal culture As CultureInfo) As Object Implements IValueConverter.ConvertBack Throw New NotSupportedException End Function End Class

    Read the article

< Previous Page | 263 264 265 266 267 268 269 270 271 272 273 274  | Next Page >