Search Results

Search found 3512 results on 141 pages for 'premature optimization'.

Page 42/141 | < Previous Page | 38 39 40 41 42 43 44 45 46 47 48 49  | Next Page >

  • How to optimize shopping carts for minimal prices?

    - by tangens
    I have a list of items I want to buy. The items are offered by different shops and different prices. The shops have individual delivery costs. I'm looking for an optimal shopping strategy (and a java library supporting it) to purchase all of the items with a minimal total price. Example: Item1 is offered at Shop1 for $100, at Shop2 for $111. Item2 is offered at Shop1 for $90, at Shop2 for $85. Delivery cost of Shop1: $10 if total order < $150; $0 otherwise Delivery cost of Shop2: $5 if total order < $50; $0 otherwise If I buy Item1 and Item2 at Shop1 the total cost is $100 + $90 +$0 = $190. If I buy Item1 and Item2 at Shop2 the total cost is $111 + $85 +$0 = $196. If I buy Item1 at Shop1 and Item2 at Shop2 the total cost is $100 + $10 + $85 + $0 = 195. I get the minimal price if I order Item1 at Shop1 and Item2 at Shop2: $195 Question I need some hints which algorithms may help me to solve optimization problems of this kind for number of items about 100 and number of shops about 20. I already looked at apache-math and its optimization package, but I have no idea what algorithm to look for.

    Read the article

  • Optimization headers for UITableView?

    - by Pask
    I have an optimization problem for the headers of a table with plain style. If I use the standard view for the table (the classic gray with titles set by titleForHeaderInSection:) everything is ok and the scrolling is smooth and immediate. When, instead, use this code to set my personal view: - (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section { return [self headerPerTitolo:[titoliSezioni objectAtIndex:section]]; } - (UIImageView *)headerPerTitolo:(NSString *)titolo { UIImageView *headerView = [[[UIImageView alloc] initWithFrame:CGRectMake(10.0, 0.0, 320.0, 44.0)] autorelease]; headerView.image = [UIImage imageNamed:kNomeImmagineHeader]; headerView.alpha = kAlphaSezioniTablePlain; UILabel * headerLabel = [[[UILabel alloc] initWithFrame:CGRectZero] autorelease]; headerLabel.backgroundColor = [UIColor clearColor]; headerLabel.opaque = NO; headerLabel.textColor = [UIColor whiteColor]; headerLabel.font = [UIFont boldSystemFontOfSize:16]; headerLabel.frame = CGRectMake(10.0,-11.0, 320.0, 44.0); headerLabel.textAlignment = UITextAlignmentLeft; headerLabel.text = titolo; [headerView addSubview:headerLabel]; return headerView; } scrolling is jerky and not immediate (sliding the finger on the screen does not match an immediate shift of the table). I do not know what caused this problem, maybe the fact that every time the method viewForHeaderInSection: is called, the code runs to create a new UIImageView. I tried many ways to solve the problem, such as creating an array of all the necessary view: apart from more time spent loading at startup, there is a continuing problem of low reactivity of the table. 've Attempted by reducing the size of UIImageView positioned from about 66 KB to 4 KB: not only has a deterioration in quality of colors (which distorts a bit 'original graphics), but ... the problem persists! Perhaps you have suggestions about it, or know me obscure techniques that enable me to optimize this aspect of my application ... I apologize for my English, I used Google for translation.

    Read the article

  • real time stock quotes, StreamReader performance optimization

    - by sean717
    I am working on a program that extracts real time quote for 900+ stocks from a website. I use HttpWebRequest to send HTTP request to the site and store the response to a stream and open a stream using the following code: HttpWebResponse response = (HttpWebResponse)request.GetResponse(); Stream stream = response.GetResponseStream (); StreamReader reader = new StreamReader( stream ) the size of the received HTML is large (5000+ lines), so it takes a long time to parse it and extract the price. For 900 files, It takes about 6 mins for parsing and extracting. Which my boss isn't happy with, he told me he'd want the whole process to be done in TWO mins. I've identified the part of the program that takes most of time to finish is parsing and extracting. I've tried to optimize the code to make it faster, the following is what I have now after some optimization: // skip lines at the top for(int i=0;i<1500;++i) reader.ReadLine(); // read the line that contains the price string theLine = reader.ReadLine(); // ... extract the price from the line now it takes about 4 mins to process all the files, there is still a significant gap to what my boss's expecting. So I am wondering, is there other way that I can further speed up the parsing and extracting and have everything done within 2 mins?

    Read the article

  • Java looping through array - Optimization

    - by oudouz
    I've got some Java code that runs quite the expected way, but it's taking some amount of time -some seconds- even if the job is just looping through an array. The input file is a Fasta file as shown in the image below. The file I'm using is 2.9Mo, and there are some other Fasta file that can take up to 20Mo. And in the code im trying to loop through it by bunches of threes, e.g: AGC TTT TCA ... etc The code has no functional sens for now but what I want is to append each Amino Acid to it's equivalent bunch of Bases. Example : AGC - Ser / CUG Leu / ... etc So what's wrong with the code ? and Is there any way to do it better ? Any optimization ? Looping through the whole String is taking some time, maybe just seconds, but need to find a better way to do it. import java.io.BufferedReader; import java.io.File; import java.io.FileNotFoundException; import java.io.FileReader; import java.io.IOException; public class fasta { public static void main(String[] args) throws IOException { File fastaFile; FileReader fastaReader; BufferedReader fastaBuffer = null; StringBuilder fastaString = new StringBuilder(); try { fastaFile = new File("res/NC_017108.fna"); fastaReader = new FileReader(fastaFile); fastaBuffer = new BufferedReader(fastaReader); String fastaDescription = fastaBuffer.readLine(); String line = fastaBuffer.readLine(); while (line != null) { fastaString.append(line); line = fastaBuffer.readLine(); } System.out.println(fastaDescription); System.out.println(); String currentFastaAcid; for (int i = 0; i < fastaString.length(); i+=3) { currentFastaAcid = fastaString.toString().substring(i, i + 3); System.out.println(currentFastaAcid); } } catch (NullPointerException e) { System.out.println(e.getMessage()); } catch (FileNotFoundException e) { System.out.println(e.getMessage()); } catch (IOException e) { System.out.println(e.getMessage()); } finally { fastaBuffer.close(); } } }

    Read the article

  • Neural Net Optimize w/ Genetic Algorithm

    - by ServAce85
    Is a genetic algorithm the most efficient way to optimize the number of hidden nodes and the amount of training done on an artificial neural network? I am coding neural networks using the NNToolbox in Matlab. I am open to any other suggestions of optimization techniques, but I'm most familiar with GA's.

    Read the article

  • Most hazardous performance bottleneck misconceptions

    - by David Murdoch
    The guys who wrote Bespin (cloud-based canvas-based code editor [and more]) recently spoke about how they re-factored and optimize a portion of the Bespin code because of a misconception that JavaScript was slow. It turned out that when all was said and done, their optimization produced no significant improvements. I'm sure many of us go out of our way to write "optimized" code based on misconceptions similar to that of the Bespin team. What are some common performance bottleneck misconceptions developers commonly subscribe to?

    Read the article

  • Mathematics - Why is Differential Calculus (MVP) in PHP a tabu?

    - by Email
    Hi I want to do a Mean-Variance-Optimization (Markowitz) but i never found anything written in php that does this. MVP needs differential calculus. Can it be done in php and why arent there any classes/works from universities? For a webapplication (regarding performance) would another language be the better choice to handle heavy calculations? Thanks so much for any help/answer on this

    Read the article

  • JavaScript tags, performance and W3C

    - by Thomas
    Today I was looking for website optimization content and I found an article talking about move JavaScript scripts to the bottom of the HTML page. Is this valid with W3C's recommendations? I learned that all JavaScript must be inside of head tag... Thank you.

    Read the article

  • Heap Behavior in C++

    - by wowus
    Is there anything wrong with the optimization of overloading the global operator new to round up all allocations to the next power of two? Theoretically, this would lower fragmentation at the cost of higher worst-case memory consumption, but does the OS already have redundant behavior with this technique, or does it do its best to conserve memory? Basically, given that memory usage isn't as much of an issue as performance, should I do this?

    Read the article

  • How can I improve the performance of this double-for print?

    - by Florenc
    I have the following static method that prints the data imported from a 40.000 lines .xls spreadsheet. Now, it takes about 27 seconds to print the data in the console and the memory consumption is huge. import org.apache.poi.hssf.usermodel.*; import org.apache.poi.ss.usermodel.*; public static void printSheetData(List<List<HSSFCell>> sheetData) { for (int i = 0; i < sheetData.size(); i++) { List<HSSFCell> list = (List<HSSFCell>) sheetData.get(i); for (int j = 0; j < list.size(); j++) { HSSFCell cell = (HSSFCell) list.get(j); System.out.print(cell.toString()); if (j < list.size() - 1) { System.out.print(", "); } } System.out.println(""); } } Disclaimer: I know, I know large data belong to a database, don't print output in the console, premature optimization is the root of all evils...

    Read the article

  • Speed comparison - Template specialization vs. Virtual Function vs. If-Statement

    - by Person
    Just to get it out of the way... Premature optimization is the root of all evil Make use of OOP etc. I understand. Just looking for some advice regarding the speed of certain operations that I can store in my grey matter for future reference. Say you have an Animation class. An animation can be looped (plays over and over) or not looped (plays once), it may have unique frame times or not, etc. Let's say there are 3 of these "either or" attributes. Note that any method of the Animation class will at most check for one of these (i.e. this isn't a case of a giant branch of if-elseif). Here are some options. 1) Give it boolean members for the attributes given above, and use an if statement to check against them when playing the animation to perform the appropriate action. Problem: Conditional checked every single time the animation is played. 2) Make a base animation class, and derive other animations classes such as LoopedAnimation and AnimationUniqueFrames, etc. Problem: Vtable check upon every call to play the animation given that you have something like a vector<Animation>. Also, making a separate class for all of the possible combinations seems code bloaty. 3) Use template specialization, and specialize those functions that depend on those attributes. Like template<bool looped, bool uniqueFrameTimes> class Animation. Problem: The problem with this is that you couldn't just have a vector<Animation> for something's animations. Could also be bloaty. I'm wondering what kind of speed each of these options offer? I'm particularly interested in the 1st and 2nd option because the 3rd doesn't allow one to iterate through a general container of Animations. In short, what is faster - a vtable fetch or a conditional?

    Read the article

  • Optimizing apache server load

    - by Jevgeni Smirnov
    We have an issue with a dedicated server load. We have 16 processors with 4 core @ 2.40GHz, if I understood correctly cat /proc/cpuinfo output. Unfortunately, I don't have access to free -m or vmstat. But from top I got that we have 24 GB. And snapshot from top about processes: As far as I see, memory is not used at all. But the cpu is used heavily. Apache consumes most of CPU. Another useful piece of information: Every 1.0s: ps u -C httpd,mysqld,php Tue Mar 27 10:48:19 2012 USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 7476 0.0 0.1 446808 37880 ? SNs Mar06 0:43 /opt/zone/sbin/httpd -D SSL -D SLOT_ID0 -f /etc/opt/zone/apache/ssl_httpd.conf mysql 36061 41.6 2.1 1113672 529876 ? SNl Feb20 21503:48 /opt/zone/sbin/mysqld --basedir=/opt/zone --datadir=/srvdata/mysql --user=mysql --log-error=/srvdata/mysql/dn79.err --pid-file=/srvdata/mysql/mysqld.pid --socket=/tmp/mysql.sock --port=3306 root 37257 0.0 0.0 424056 16840 ? SNs Mar22 1:03 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 52743 0.0 0.1 447100 30360 ? SN 10:40 0:00 /opt/zone/sbin/httpd -D SSL -D SLOT_ID0 -f /etc/opt/zone/apache/ssl_httpd.conf http 52744 0.0 0.1 447100 30360 ? SN 10:40 0:00 /opt/zone/sbin/httpd -D SSL -D SLOT_ID0 -f /etc/opt/zone/apache/ssl_httpd.conf http 52745 0.0 0.1 447100 30360 ? SN 10:40 0:00 /opt/zone/sbin/httpd -D SSL -D SLOT_ID0 -f /etc/opt/zone/apache/ssl_httpd.conf http 52746 0.0 0.1 447100 30360 ? SN 10:40 0:00 /opt/zone/sbin/httpd -D SSL -D SLOT_ID0 -f /etc/opt/zone/apache/ssl_httpd.conf http 52747 0.0 0.1 446956 30324 ? SN 10:40 0:00 /opt/zone/sbin/httpd -D SSL -D SLOT_ID0 -f /etc/opt/zone/apache/ssl_httpd.conf http 52980 69.1 1.8 852468 458088 ? RN 10:41 5:02 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 53483 47.0 0.8 615088 221040 ? RN 10:43 2:05 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 53641 1.8 0.2 446580 54632 ? SN 10:45 0:03 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54384 81.2 0.9 625828 229972 ? RN 10:45 2:14 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54411 47.7 0.5 535992 142416 ? RN 10:45 1:09 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54470 41.7 0.4 512528 120012 ? RN 10:46 0:54 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54475 0.1 0.1 437016 41528 ? SN 10:46 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54486 1.5 0.2 445636 53916 ? SN 10:46 0:02 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54531 2.5 0.2 445424 53012 ? SN 10:46 0:02 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54549 0.0 0.0 424188 9188 ? SN 10:46 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54642 0.0 0.0 424188 9200 ? SN 10:47 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54651 0.0 0.0 424188 9188 ? SN 10:47 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54661 0.0 0.0 424188 9208 ? SN 10:47 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54663 6.9 0.2 449936 58560 ? SN 10:47 0:03 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54666 6.0 0.2 453356 61124 ? SN 10:47 0:02 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54667 2.8 0.1 437608 42088 ? SN 10:47 0:01 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54670 1.5 0.1 437540 42172 ? SN 10:47 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54672 2.1 0.1 439076 43648 ? SN 10:47 0:01 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54709 0.0 0.0 424188 9192 ? SN 10:47 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54711 1.0 0.1 437284 41780 ? SN 10:47 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54712 11.8 0.2 448172 54700 ? SN 10:47 0:02 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54720 0.0 0.0 424188 9192 ? SN 10:48 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54721 0.0 0.0 424188 9188 ? SN 10:48 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54747 9.1 0.2 443568 51848 ? SN 10:48 0:01 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54782 1.8 0.1 438708 37896 ? RN 10:48 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54784 0.0 0.0 424188 9180 ? SN 10:48 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54785 0.0 0.0 424188 9188 ? SN 10:48 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54789 0.0 0.0 424188 9188 ? SN 10:48 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54790 0.0 0.0 424188 9188 ? SN 10:48 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54791 0.0 0.0 424188 9188 ? SN 10:48 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 http 54792 0.0 0.0 424056 8352 ? SN 10:48 0:00 /opt/zone/sbin/httpd -f /etc/opt/zone/apache/httpd.conf -D SLOT_ID0 Webalizer shows following: What can be done in the following situation? The application is Magento.

    Read the article

  • PostgreSQL lots of writes

    - by strife911
    Hi, I am using postgreSQL for a scientific application (unsupervised clustering). The python program is multi-threaded so that each thread manages its own postmaster process (one per core). Hence, their is a lot of concurrency. Each thread-process loop infinitely though two SQL queries. The first is for reading, the second is for writing. The read operation considers 500 time the amount of rows the write operation considers. Here is the output of dstat: ----total-cpu-usage---- ------memory-usage----- -dsk/total- --paging-- --io/total- usr sys idl wai hiq siq| used buff cach free| read writ| in out | read writ 4 0 32 64 0 0|3599M 63M 57G 1893M|1524k 16M| 0 0 | 98 2046 1 0 35 64 0 0|3599M 63M 57G 1892M|1204k 17M| 0 0 | 68 2062 2 0 32 66 0 0|3599M 63M 57G 1890M|1132k 17M| 0 0 | 62 2033 2 1 32 65 0 0|3599M 63M 57G 1904M|1236k 18M| 0 0 | 80 1994 2 0 31 67 0 0|3599M 63M 57G 1903M|1312k 16M| 0 0 | 70 1900 2 0 37 60 0 0|3599M 63M 57G 1899M|1116k 15M| 0 0 | 71 1594 2 1 37 60 0 0|3599M 63M 57G 1898M| 448k 17M| 0 0 | 39 2001 2 0 25 72 0 0|3599M 63M 57G 1896M|1192k 17M| 0 0 | 78 1946 1 0 40 58 0 0|3599M 63M 57G 1895M| 432k 15M| 0 0 | 38 1937 I am pretty sure I could write more often than that for I have seen it write up to 110-140M on dstat. How can I optimize this process?

    Read the article

  • XDEBUG/PHP doesn't dump profile even when set up properly?

    - by John D.
    I installed xdebug from source, but also tried my package manager (separately) and they both are loaded correctly (verified by restarting Apache and seeing the xdebug copyright info in phpinfo()) but they do not dump profiling information. Out of the 40 different attempts of configuration it logged once or twice but I lost what I did, I tried with first only loading the module in php.ini with no settings, but it didn't log to /tmp/. I tried many different settings but my current is now: xdebug.profiler_enable = Off xdebug.profiler_enable_trigger = 1 xdebug.profiler_output_dir = "/tmp/" xdebug.profiler_output_name = "profiler.%t" Of course I call my script through 127.0.0.1/test.php?XDEBUG_PROFILE, which is for enable_trigger. Do you know why it would not dump profiler information? nobody (Arch Linux) can write to /tmp/ as it has before, so I'm sure it is not a permissions error. Apache's error_log does not tell me anything about xdebug either, as it has loaded correctly. It just does not "work"! EDIT: I made a subfolder "xdebug_profiles" in /tmp/ and chown'ed it to nobody, and now it works flawlessly. I'm not sure why it couldn't write before, I guess it's just a caveat with nobody on Arch. I answered my own question , not enough points to answer it or comment, so consider this answered.

    Read the article

  • CPU's on Hyper-V host system is just idling, even though VM's are at full throttle

    - by Bjørn
    Hello, I have a server that is running Windows 2008 64 bit Hyper-V, with 8 gigs of RAM and Intel Xeon X3440 @ 2.53 Ghz, which gives me 8 logical cores in the performance monitor on the host system. I have set up three Virtual Machines, all running Windows 2008 32 bit. Build server, running Team City Staging server SQL Server, running SQL Server 2005 These three machines are running very sluggishly, they are at 100% cpu even though the host system is barely using any cpu at all, typically below 10% total. Could anyone please give some tips as to the best setup for CPU allocating? Should I have set each server to have two cores, or should I increase this number above the total number of cores on the host? What is a good number to set on the Virtual Machine Reserve and Virtual Machine Limit? Is 8 gigs of physical RAM insufficient for 3 VM's? Thanks for reading. :)

    Read the article

  • Serving images from another hostname vs Apache overload for the rewrites

    - by luison
    We are trying to improve further the speed of some sites with older HTML in order as well to obtain better SEO results. We have now applied some minify measures, combined html, css etc. We use a small virtualized infrastructure and we've always wanted to use a light + standar http server configuration so the first one can serve images and static contents vs the other one php, rewrites, etc. We can easily do that now with a VM using the same files and conf of vhosts (bind mounts) on apache but with hardly any modules loaded. This means the light httpd will have smaller fingerprint that would allow us to serve more and quicker, have more minSpareServer running, etc. So, as browsers benefit from loading static content from different hostnames as well, we've thought about building a rewrite rule on our main server (main.com) to "redirect" all images and css *.jpg, *.gif, *.css etc to the same at say cdn.main.com thus the browser being able to have more connections. The question is, assuming we have a very complex rewrite ruleset already (we manually manipulate many old URLs for SEO) will it be worth? I mean will the additional load of main's apache to have to redirect main.com/image.jpg (I understand we'll have to do a 301) to cdn.main.com/image.jpg + then cdn.main.com having to serve it, be larger than the gain we would be archiving on the browser? Could the excess of 301s of all images on a page be penalized by google? How do large companies work this out, does the original code already include images linked from the cdn with absolute paths? EDIT Just to clarify, our concern is not to do so much with server performance or bandwith. We could obviously employ an external CDN server but we have plenty CPU and bandwith. Our concern is with how to have "old" sites with plenty semi-static HTML content benefiting from splitting connections for images and static content via apache without having to change the html to absolute paths (ie. image.jpg to cdn.main.com/image.jpg happening on the server not the code)

    Read the article

  • Disable Memory Modules In BIOS for Testing Purposes (Optimize Nehalem/Gulftown Memory Performance)

    - by Bob
    I recently acquired an HP Z800 with two Intel Xeon X5650 (Gulftown) 6 core processors. The person that configured the system chose 16GB (8 x 2GB DDR3-1333). I'm assuming this person was unaware these processors have 3 memory channels and to optimize memory performance one should choose memory in multiples of three. Based on this information, I have a question: By entering the BIOS, can I disable the bank on each processor that has the single memory module? If so, will this have any adverse effects or behave differently than physically removing the modules? I ask due to the fact that I prefer to store the extra memory in the system if it truly behaves as if the memory is not even there. Also, I see this as an opportunity to test 12GB vs. 16GB to see if there is a noticeable difference. Note: According to http://www.delltechcenter.com/page/04-08-2009+-+Nehalem+and+Memory+Configurations?t=anon, the current configuration reduces the overall data transfer speed to 1066 and in addition, the memory bandwidth goes down by about 23%.

    Read the article

  • Optimizing MySQL for small VPS

    - by Chris M
    I'm trying to optimize my MySQL config for a verrry small VPS. The VPS is also running NGINX/PHP-FPM and Magento; all with a limit of 250MB of RAM. This is an output of MySQL Tuner... -------- General Statistics -------------------------------------------------- [--] Skipped version check for MySQLTuner script [OK] Currently running supported MySQL version 5.1.41-3ubuntu12.8 [OK] Operating on 64-bit architecture -------- Storage Engine Statistics ------------------------------------------- [--] Status: -Archive -BDB -Federated +InnoDB -ISAM -NDBCluster [--] Data in MyISAM tables: 1M (Tables: 14) [--] Data in InnoDB tables: 29M (Tables: 301) [--] Data in MEMORY tables: 1M (Tables: 17) [!!] Total fragmented tables: 301 -------- Security Recommendations ------------------------------------------- [OK] All database users have passwords assigned -------- Performance Metrics ------------------------------------------------- [--] Up for: 2d 11h 14m 58s (1M q [8.038 qps], 33K conn, TX: 2B, RX: 618M) [--] Reads / Writes: 83% / 17% [--] Total buffers: 122.0M global + 8.6M per thread (100 max threads) [!!] Maximum possible memory usage: 978.2M (404% of installed RAM) [OK] Slow queries: 0% (37/1M) [OK] Highest usage of available connections: 6% (6/100) [OK] Key buffer size / total MyISAM indexes: 32.0M/282.0K [OK] Key buffer hit rate: 99.7% (358K cached / 1K reads) [OK] Query cache efficiency: 83.4% (1M cached / 1M selects) [!!] Query cache prunes per day: 48301 [OK] Sorts requiring temporary tables: 0% (0 temp sorts / 144K sorts) [OK] Temporary tables created on disk: 13% (27K on disk / 203K total) [OK] Thread cache hit rate: 99% (6 created / 33K connections) [!!] Table cache hit rate: 0% (32 open / 51K opened) [OK] Open file limit used: 1% (20/1K) [OK] Table locks acquired immediately: 99% (1M immediate / 1M locks) [!!] InnoDB data size / buffer pool: 29.2M/8.0M -------- Recommendations ----------------------------------------------------- General recommendations: Run OPTIMIZE TABLE to defragment tables for better performance Reduce your overall MySQL memory footprint for system stability Enable the slow query log to troubleshoot bad queries Increase table_cache gradually to avoid file descriptor limits Variables to adjust: *** MySQL's maximum memory usage is dangerously high *** *** Add RAM before increasing MySQL buffer variables *** query_cache_size (> 64M) table_cache (> 32) innodb_buffer_pool_size (>= 29M) and this is the config. # # The MySQL database server configuration file. # # You can copy this to one of: # - "/etc/mysql/my.cnf" to set global options, # - "~/.my.cnf" to set user-specific options. # # One can use all long options that the program supports. # Run program with --help to get a list of available options and with # --print-defaults to see which it would actually understand and use. # # For explanations see # http://dev.mysql.com/doc/mysql/en/server-system-variables.html # This will be passed to all mysql clients # It has been reported that passwords should be enclosed with ticks/quotes # escpecially if they contain "#" chars... # Remember to edit /etc/mysql/debian.cnf when changing the socket location. [client] port = 3306 socket = /var/run/mysqld/mysqld.sock # Here is entries for some specific programs # The following values assume you have at least 32M ram # This was formally known as [safe_mysqld]. Both versions are currently parsed. [mysqld_safe] socket = /var/run/mysqld/mysqld.sock nice = 0 [mysqld] # # * Basic Settings # # # * IMPORTANT # If you make changes to these settings and your system uses apparmor, you may # also need to also adjust /etc/apparmor.d/usr.sbin.mysqld. # user = mysql socket = /var/run/mysqld/mysqld.sock port = 3306 basedir = /usr datadir = /var/lib/mysql tmpdir = /tmp skip-external-locking # # Instead of skip-networking the default is now to listen only on # localhost which is more compatible and is not less secure. bind-address = 127.0.0.1 # # * Fine Tuning # key_buffer = 32M max_allowed_packet = 16M thread_stack = 192K thread_cache_size = 8 sort_buffer_size = 4M read_buffer_size = 4M myisam_sort_buffer_size = 16M # This replaces the startup script and checks MyISAM tables if needed # the first time they are touched myisam-recover = BACKUP max_connections = 100 table_cache = 32 tmp_table_size = 128M #thread_concurrency = 10 # # * Query Cache Configuration # #query_cache_limit = 1M query_cache_type = 1 query_cache_size = 64M # # * Logging and Replication # # Both location gets rotated by the cronjob. # Be aware that this log type is a performance killer. # As of 5.1 you can enable the log at runtime! #general_log_file = /var/log/mysql/mysql.log #general_log = 1 log_error = /var/log/mysql/error.log # Here you can see queries with especially long duration #log_slow_queries = /var/log/mysql/mysql-slow.log #long_query_time = 2 #log-queries-not-using-indexes # # The following can be used as easy to replay backup logs or for replication. # note: if you are setting up a replication slave, see README.Debian about # other settings you may need to change. #server-id = 1 #log_bin = /var/log/mysql/mysql-bin.log expire_logs_days = 10 max_binlog_size = 100M #binlog_do_db = include_database_name #binlog_ignore_db = include_database_name # # * InnoDB # # InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/. # Read the manual for more InnoDB related options. There are many! # # * Security Features # # Read the manual, too, if you want chroot! # chroot = /var/lib/mysql/ # # For generating SSL certificates I recommend the OpenSSL GUI "tinyca". # # ssl-ca=/etc/mysql/cacert.pem # ssl-cert=/etc/mysql/server-cert.pem # ssl-key=/etc/mysql/server-key.pem [mysqldump] quick quote-names max_allowed_packet = 16M [mysql] #no-auto-rehash # faster start of mysql but no tab completition [isamchk] key_buffer = 16M # # * IMPORTANT: Additional settings that can override those from this file! # The files must end with '.cnf', otherwise they'll be ignored. # !includedir /etc/mysql/conf.d/ The site contains 1 wordpress site,so lots of MYISAM but mostly static content as its not changing all that often (A wordpress cache plugin deals with this). And the Magento Site which consists of a lot of InnoDB tables, some MyISAM and some INMEMORY. The "read" side seems to be running pretty well with a mass of optimizations I've used on Magento, the NGINX setup and PHP-FPM + XCACHE. I'd love to have a kick in the right direction with the MySQL config so I'm not blindly altering it based on the MySQLTuner without understanding what I'm changing. Thanks

    Read the article

  • Monitoring outgoing bandwidth of application

    - by jnolte
    I currently have a VPS that is consuming a ton of outgoing bandwidth and I am trying to drill down to where this may be coming from. Does anyone know of a logical way to go about finding out which pages on the site are consuming the most outgoing data. We have done a ton of front-end optimizations to the site and our google page speed rankings ar 85% so I feel we have done a pretty great job at optimizing the site for speed. Can someone lend some insight on how they have made similar optimizations? Application / Server Stack LEMP Running Varnish Cache / PHP5-FPM WordPress running w3 Total Cache Ubuntu 12.04 LTS

    Read the article

  • Better way to design a database

    - by cMinor
    I have a conceptual problem and I would like to get your ideas on how I'll be able to do what I am aiming. My goal is to create a database with information of persons who work at a place depending on their profession and skills,and keep control of salary and projects (how much would cost summing all the hours of work) I have 3 categories which can have subcategories: Outsourcing Technician welder turner assistant Administrative supervisor manager So each person has its information and the projects they are working on, also one person may do several jobs... I was thinking about having 5 tables (EMPLOYEE, SKILLS, PROYECTS, SALARY, PROFESSION) but I guess there is a better way of doing this. create table Employee ( PRIMARY KEY [Person_ID] int(10), [Name] varchar(30), [sex] varchar(10), [address] varchar(10), [profession] varchar(10), [Skills_ID] int(10), [Proyect_ID] int(10), [Salary_ID] int(10), [Salary] float ) create table Skills ( PRIMARY KEY [Skills_ID] int(10), FOREIGN KEY [Skills_name] varchar(10) REFERENCES Employee(Person_ID), [Skills_pay] float(10), [Comments] varchar(50) ) create table Proyects ( PRIMARY KEY [Proyect_ID] int(10), FOREIGN KEY [Skills_name] varchar(10) REFERENCES Employee(Person_ID) [Proyect_name] varchar(10), [working_Hours] float(10), [Comments] varchar(50) ) create table Salary ( PRIMARY KEY [Salary_ID] int(10), FOREIGN KEY [Skills_name] varchar(10) REFERENCES Employee(Person_ID) [Proyect_name] varchar(10), [working_Hours] float(10), [Comments] varchar(50) ) So to get the total amount of the cost of a project I would just sum the working hours of each employee envolved and sum some extra costs in an aggregate query. Is there a way to do this in a more efficient way? What to add or delete of this small model? I guess I am missing something in the salary - maybe I need another table for that?

    Read the article

  • Looking for a short term solution to improve website performance with additional server

    - by Tanim Mirza
    I am working with a small team to run an internal website running with PHP 5.3.9, MySQL 5.0.77. All the files and database are hosted on a dedicated Linux machine with the following configuration: Intel Xeon E5450 8 CPU cores @3.00GHz, 2992.498 MHz, Cache 6148 KB, Cent OS – Red Hat Enterprise Linux Server release 5.4 We started small and then the database got bigger and now the website performance degraded significantly. We often get server space overrun, mysql overloaded with too many calls, etc. We don't have much experience dealing with these issues. We recently got another server that we were thinking to use to improve performance. Since it has better configuration, some of us wanted to completely move everything to the new machine. But I am trying to find out how we can utilize both machine for optimized performance. I found options such as MySQL clustering, Load balancer, etc. I was wondering if I could get any suggestion for this situation "How to utilize two machines in short term for best performance", that would be great. By short term we are looking for something that we can deploy in a month or so. Thanks in advance for your time.

    Read the article

  • Optimize windows 2008 performance

    - by Giorgi
    Hello, I have windows server 2008 sp2 installed as virtual machine on my personal laptop. I use it only for source control (visual svn) and continuous integration (teamcity). As the virtual machine resources are limited I'd like to optimize it's performance by disabling services and features that are not necessary for my purposes. Can anyone recommend where to start or provide with tips for getting better performance. Thanks.

    Read the article

  • Open Source Scheduling Software?

    - by Kaiser Advisor
    Hi Everyone, I'm looking for scheduling software to schedule 25 people over 8 work sites. Most are FT and can work up to 40 hours a week, but some are part-time and can only work certain days of the week and up to a certain number of hours a week. There are 3 classes of employees: Managers, Supervisors, and Workers. They should be shuffled so that they spend approximately equal time at each of the 8 work sites and with all classes of employees; i.e., Joe the worker should spend about 1 out of 8 days on each work site, and work with managers, supervisors, and other workers equally. I tried to do this in excel with the solver, but the shuffling requirement makes it way too complicated, so I'm stuck trying to do big parts of this manually with the solver helping out with just the hour provisioning piece. Is there any open source software that could help me? Much appreciated! KA

    Read the article

< Previous Page | 38 39 40 41 42 43 44 45 46 47 48 49  | Next Page >