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For more on tuning Eclipse JVM heap size, you can refer to this IBM article
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Using local XSD's when no internet connection is available, or you are using another version than the one online
Eclipse uses XSD files to check XML files for correctness and also when using autocompletion. Normally, eclipse uses the XSD location specified at the top of the XML file which is usually a remote address. If you do not have an internet connection, the XSD will not be found and these features will not be available (unless they have been previously cached by eclipse).
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