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PODesign decision? 4 minute report... tying up the server
 

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  1. PODesign decision? 4 minute report... tying up the server
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    <p>I have a few reports that are taking up to 4 minutes to run in my RoR application. Since then, my users are experiencing delays with their simple tasks in the systems where the system stops responding.</p> <p>I am still trying to look into the main cause of the issue to see if the reporting and the system-hangs are related. Does anyone have any advise on how I should go about restructing my report to it does not take 4 minutes to run?</p> <p>So far I have looked into running a background job every night that calculates all of the figures I want so the reporting times will be significantly decreased. I am yet to find a solution that may use middleware or in memory instances to derive reports instead of hitting the DB with a large query.</p> <p><strong>Technical info:</strong></p> <ul> <li>The VPS is running 384 MB of RAM (will an increase be a suficient work-around?)</li> <li>The reports are a combination of SQLs with some heavy ruby scripting to massage the contents so they are displayed in a readible fashion</li> <li>DB tables contain between 2,000 to 30,000 rows</li> </ul> <p><strong>Technical Report Info</strong></p> <ol> <li>DB-query-1 has 5 inner joins. It is run first to create a lookup hash</li> <li>DB-query-2 has 5 inner joins. It is run once and each record of its resultset is traversed</li> <li>For each record of (2.), DB-query-3 (containing 5 inner joins) is run</li> <li>For each record of (2.), the lookup hash from (1.) is traversed to perform some calculations</li> </ol> <p>From writing this through Anon's request of additional information I can already see the sting of a nested loop... </p>
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    1. USCoderama
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    1. COAbout how many queries do you run for each report? How large are the tables you're hitting? What sort of stuff are you doing in Ruby (anything heavy, like sorting?)
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    2. COAdded additional info - thanks
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    3. COWould it be possible to roll (3) into (2)? That would really cut down the number of queries being performed.
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      1. USAnon.
 

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