ID 582204 - Scrubbing cached frames can be slow when postage stamps are enabled/set to "current frame"

Problem summary
Scrubbing cached frames can be slow when postage stamps are enabled/set to "current frame".
This happens despite the frames being able to playback in realtime.
 
Customer reported version
Nuke 14.0v5
 
Customer reported platform
ubuntu
 
Steps to reproduce
 
1) Open Nuke.
 
2) Read in the attached files (a 4K EXR sequence) from a network location.
 
3) Play back some of the frames to cache them. Once they are cached, they should play back in realtime.
 
4) Stop playback and then scrub along the cached frames in the Viewer.
 
Expected behaviour
Scrubbing should be smooth on cached frames.
 
Actual behaviour
Scrubbing along the cached frames is slow.
 
Workaround
Either disable postage stamps on the node by opening the Read node's control panel, navigating to the Node tab and unchecking Postage Stamp.
Alternatively, set the postage stamps to static frame by navigating to Edit > Preferences > Node Graph and changing postage stamp mode to Static frame.
 
Reproduced by support
This bug has been reproduced in:
Nuke 15.1v1 - Windows 11
Nuke 12.0v1 - Windows 11
 
Unable to reproduce bug in:
Nuke 15.1v1 - macOS 14.5 (Sonoma) - Linux Rocky 9
 
Earliest version tested
Nuke 12.0v1 - Windows 11
- This issue appears to be in all tested versions of the product on Windows 11.