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It is strongly recommended that Solr runs on a 64-bit Java. A 64-bit Java requires a 64-bit operating system, and a 64-bit operating system requires a 64-bit CPU. There's nothing wrong with 32-bit software or hardware, but a 32-bit Java is limited to a 2GB heap, which can result in artificial limitations that don't exist with a larger heap. . It is very easy to build an index that will not function at all if the heap cannot be made larger than 2GB. The Java heap is discussed in a later section of this page.
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