Thanks for your inquiry. It is quite difficult to answer such questions because CPU performance and memory usage all depend on complexity and size of the documents you are loading/generating.
In terms of memory, Aspose.Words does not have any limitations. If you’re loading huge Word documents into Aspose.Words’ DOM, more memory would be required. This is because during processing, the document needs to be held wholly in memory. Usually, Aspose.Words needs 10 times more memory than the original document size to build a DOM in the memory.
While rendering a document to fixed page formats (e.g. PDF, Jpeg, Xps), Aspose.Words needs to build two model in the memory – one for document and the other for rendered document.
The process of building layout model is not linear; it may take a minute to render one page and may take a few seconds to render 100 pages. Also, Aspose.Words has to create APS (Aspose Page Specification) model in memory and this may again eat some more time for some documents. Rest assured, we’re always working on improving performance; but, rendering will be always running slower than simple saving to flow formats (e.g doc/docx).