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Performance concerns

Hi, we’ve been testing the dll with some big files and are a litle bit concerned about performance.

PDF files with images embedded on it (that end up weighing 2-3 mbs or more) are taking 10+ secs to render per page (we’re using the aproach explained at

Our users will, surely, use even bigger files (around 40-50 mbs), since they scan files and generate large PDF and others.

Is there something we can do to increase the performance? We realize the files are way too big, but we cannot ask users to shrink them.

Getting the image (instead of the html) is any faster?


Hi Sebastian,

Thanks for taking interest in GroupDocs.Viewer for .NET.

The document rendering time depends on multiple factors such as document’s content which can include text, images, tables; amount of resources that application can use; server loading and so on. However, to increase the performance and reduce the document rendering time the API provides cache feature. When GroupDocs.Viewer cache is enabled (ViewerConfig.UseCache = true), it consumes more resources and time when you render the document for the first time. Whereas, when you render the same document for the second time, the API extracts data from the cache and rendering time reduces considerably.

Furthermore, you can visit Performance Profile of the latest version of GroupDocs.Viewer for .NET to compare the performance of image based rendering and HTML based rendering.

In case of any further questions, please feel free to let us know.

Warm Regards