Working Effectively with Large Documents

This section gives high-level guidelines to achieve fast end-user interaction with source documents which contain hundreds or even thousands of pages.

Use Viewing Packages to Pre-Convert Content Whenever Possible

The most important thing you can do to make large documents load quickly in the browser is to make sure the document content has already been converted for viewing in the browser before an end user starts to view it. This is especially true for Microsoft Office documents.

If you are using PrizmDoc Application Services (PAS), you can take advantage of our Viewing Packages feature to comprehensively pre-convert an entire document for fast viewing in the browser. Once created, a viewing package persists until you explicitly delete it, and it allows the PrizmDoc Application Services to simply return static content for any page of a document, even if the document has thousands of pages.

If you are not yet taking advantage of the PrizmDoc Application Services (that is, you are communicating directly to the back-end PrizmDoc Server to create your viewing sessions), consider adding PrizmDoc Application Services to your environment to take advantage of the Viewing Packages feature.

If you are not familiar with how the browser, your web tier, PrizmDoc Application Services, and the back-end PrizmDoc Server work together, refer to the Understanding PrizmDoc overview.

Use Server-side Search to View Large Documents

Our Viewing Client allows end users to easily search a document and navigate to the results. When the full text of a document can fit into browser memory, the Viewing Client can simply perform the search on the client-side in the browser. However, if the amount of text in a document is sufficiently large, the client-side search is not possible. Fortunately, with the new Server-side Search option, our Viewing Client has the ability to offload search work to the server and populate the Viewing Client UI as results become available. This new feature enables processing of much larger documents than previously possible.

Considerations for using Server-side Search Option

With PrizmDoc v12.0, we have added a new option of processing document text that enables processing of much larger documents than previously possible. In addition to many browser optimizations we have made, there are significant changes under the hood for producing server-side search text. Since this is such a significant change, we have turned this feature off by default in PrizmDoc v12.0. This will allow you to evaluate and test this feature with no risk and determine whether it is right for you. In this release, there are some tradeoffs that you should be aware of as discussed below. As we refine this feature in subsequent releases, we expect these tradeoffs to be eliminated and eventually this will be the only mode for generating text.

Benefits of using this Option

Previous versions of PrizmDoc could fail to convert or extract all text in large documents, such as PDFs over 1000 pages, and 250+ page Word documents. If you process documents with a large number of pages, this feature will likely benefit you.
Search results on large documents are much faster using server-side search mode.

System Implications

System Resources - Converting large documents is very resource intensive, particularly with Office documents. Specifically, the number of system cores will have a direct effect on performance. For example, a 1000 page Word document may take several minutes to complete text extraction. This process may be fully utilizing 2 cores during that conversion. So 3-4 concurrent users, each converting a 1000 page document, would consume all conversion resources on that server during that time. Subsequent users attempting to convert documents during this time may encounter errors until the system resources are released by the completed text extraction process. This may result in a sub-optimal user experience when resources are overloaded. We strongly recommend servers with a large number of cores if you are working frequently with large documents.
Abandoned Viewing Sessions - The text extraction process will continue if a user abandons a session before the text extraction process completes. This will be improved in a subsequent release, but it is important to know that a user abandoning a document does not necessarily release conversion resources on the server.
Viewing Smaller Documents - Our performance tests in both modes reveal nominal performance and resource differences when viewing smaller documents. Converting Office documents with server-side search mode enabled will consume roughly 10% more resources.

Client-side vs. Server-side Search (with Server-side Search Option enabled)

Ideally, the Viewing Client would perform a client-side search whenever possible and a server-side search whenever necessary. In reality, we make an educated guess based on page count. By default, our Viewing Client will perform a client-side search if a document contains no more than 80 pages; otherwise, the Viewing Client will offload the search work to the server (when Server-side Search is enabled). For many kinds of documents this arbitrary 80-page threshold works fine. However, if you are using documents of 80 pages or less with a substantial amount of text, or if your end user's browser is particularly memory constrained, you may find that this default is not aggressive enough in offloading search work to the server.

When constructing a viewer control, you can use the ViewerControlOptions searchMethodPageCountThreshold property to adjust the maximum number of pages a document can have before the Viewing Client switches to server-side search. Additionally, you can use the searchMethodType property to force the Viewing Client to only use server-side search (or only use client-side search).