These are the factors which affect the performance of magento :
1. EAV structure of magento database, even for retrieving single entity the query becomes very complex .
2. Magento’s template system involves a lot of recursive rendering
3. Huge XML trees built up for layout configuration, application configuration settings
for more tips and tutorial about magento visit : http://www.ilovemage.com/learn-magen...velopment.html
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