[Patrick Jones] “I noticed that the Render was crazy fast, and it was punhy. Although I still hate with a passion the magnet timeline, and it does slow me down on my creative process, it was sort of worth it.
6 months in, and I feel it’s not rendering as fast.. Nothing changed.
I still work off my RAID 5. Have over 50% available. My Libraries are under 10 Events (usually 3 Project with each Library). Should I upgrade my Interal to an 1+TB SSD”
I’ve edited a 20TB 4k H264 documentary on a 2015 iMac 27 like yours, using proxies, with material on a Thunderbay 4. It worked mostly OK, and that was without using background rendering.
When you say “render was crazy fast”, then “it’s not rendering as fast”, do you mean export or rendering the timeline with CTRL+R? If export, what codec, and what is your editing codec?
Have you added any compute-intensive effects? Those will slow things way down and have little to do with I/O.
You can check your machine and software config by simply creating a test library, importing a 4k/30 H264 test clip, add no effects or edits, then exporting that as 4k/30 H264 this way: File>Share>Master File>Settings, Format: Computer, Video codec: H.264 Faster Encode, Resolution: either 4k or 1080p.
If that is as fast as expected, then maybe it’s something you’ve done to the production timeline or library. As edits gradually accumulate in a timeline, things can slow down. To some degree that’s normal.
If you were previously editing 4k on a 1080p timeline, then switch to a 4k timeline, the render files will become 4k so certain things will be slower. You can usually edit 4k on a 1080p timeline, then if you need 4k output, switch the project characteristics back to 4k before you export.
However for 4k H264 the 2015 iMac is not as fast as the 2017. Apparently due to improvements in the Kaby Lake version of Quick Sync or in how FCPX uses this, it’s about 2x faster at H264 operations, including timeline scrubbing and export.