At Synergy 2010 Citrix announced Project Nitro. Project Nitro is a group of projects for the next generation of Citrix HDX technologies focused on increased performance and efficiency. Project Laser is the printing aspect of this effort and has now been released for XenApp 6. It is posted on the MyCitrix download site as the XenApp 6 printing optimization pack. While it will eventually be built into XenApp, it is already built into the upcoming release of XenDesktop 5.

Rich graphical applications and content naturally lead to larger print jobs. The content of the print spool files created by such applications are dominated by embedded fonts and images. This is where these optimizations will shine, especially when using universal printing with client and host connected though a wide area network.

Embedded images are particularly troublesome because they can be quite large and they can actually appear many times within the same EMF print stream. So the print payloads for applications like Microsoft PowerPoint, Adobe Acrobat Reader, Adobe Photoshop and other image manipulation programs (GIS apps, high end graphics/CAD) will benefit immensely from these improvements. For these graphically intense applications, it is not uncommon to see really large print streams (hundreds of megabytes or more) which we are now able to compress to as little as 1% of the original size.

There is a variation in how much these enhancements will affect print payloads. For example, a Microsoft Excel document composed entirely of lines, text, and basic graphics like a pie chart or bar graph may not see such significant improvement. Microsoft Word documents may see some impact depending upon how many images are embedded and how many different fonts are referenced. Like Microsoft Word documents, web browser printing improvements depends on the mix of images/text in the underlying web page. However web content does tend to have more images embedded along with a wider variety of fonts than a Word document might.

So your mileage may vary anywhere from no change to as much as 99% less data being downloaded to client depending upon what kind of workload you throw at it. Unfortunately it is very hard to generalize. But the key highlights will be:

  • Up to 90+ % reduction in delivered UPD print data for the most demanding printing applications
  • Adaptive caching of embedded images/fonts so frequently referenced fonts and images are only downloaded once
  • Administrative controls to further reduce print job size by applying slight reductions in print quality

On LANs, the difference in print speed may not be noticeable since mechanical and printer firmware processing delays dominate. On slow or latent networks, the difference could be dramatic depending upon how big the original print stream was and how slow the network is. But in the end, we will be moving upwards of 90 % less data for graphically intense print content. Who’s not going to be happy about that?

Another important part of the Project Laser enhancements is the introduction of dynamic printer discovery. This enables us to refresh the redirected client printers in the session (including the default printer) without requiring the session to be restarted or recreated. Redirected printers are discovered dynamically and created automatically. This means that printers plugged-in or connected wirelessly on the end-point will automatically show up in a remote session. More importantly, the pass through client also monitors for changes to printing environment and similarly notifies upstream XenApp hosts. So when a roaming desktop user moves from one end-point to another, the reconfigured print environment from their desktop session is automatically propagated to their XenApp hosted applications.

Finally, we have also added some goodies to our printing policies that will allow administrators to exert more control over auto-created printers, whether they are network printers or redirected client printers. Aside from new controls of Laser printing optimizations, there are also controls to override common settings when printers are created, limit the print quality and image compression options available to users, and force UPD printing logic on the client to reprocess an EMF print stream rather than spooling EMF directly. This last item is a compatibility option needed for some applications and drivers. In prior releases, this could only be set by registry key preference on the client. Now it can be controlled by policy applied to the host session.

So there is no need for you to just sit there and accept the slow printing pain anymore. Go download and give it a go and see how much better it can improve your printing experience.