RUBiS Design Review William Pugh Boy this sucks Papers show that EJB has much worse performance than JDBC or PHP Don t know why need to get their experiments up and running But boy does their EJB implementation suck Only looked at the EJB 2 0 local interface implementation Design Uses Entity beans to represent persistent state Use SessionFacade to access entity beans Uses bean managed transactions no container managed relationships manual authentication in each session bean Entity Beans No homes cached multiple JNDI lookups performed for most business method 6 JNDI lookups performed for SB AboutMe getAboutMe How should we do it do in ejbPostCreate ejbActivate Static Singleton hard to make this work in EJB world Transactions Transactions used for lots of read only business methods SearchItemsByCategory SearchItemsByRegion BrowseCategories BrowseRegions AboutMe Transaction Collapse In paper JBoss falls down when transactions start timing out presumably system was slowing down to the point where transactions were taking too long What was the transaction timeout How to handle overload in transaction environment timeout and rollback obviously don t work better to just immediately fail some transactions Transaction Collapse Before collapse most operations pretty fast After collapse three operations are never fast BrowseCategories BrowseCategoriesInRegion SelectCategoryToSellItem
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