If submitting via the desktop client, are you using a custom driver or the generic upload driver? A custom driver will be printed "as-is" when released, which significantly improves performance. The generic driver submisission is always re-rendered at release time, which requires the job to go through the converison process.
If submitting jobs via the mobile app or email, a PDF will print faster if the printer can natively print PDF files. If the printer is capable of supporting PDF files directly, you can change the printer language preference for the given printer in XWC in the printers details page. If PDF is pushed to the top of the list, a mobile PDF job will not need to be converted and can be sent directly to the printer which improves performance.
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