I don't know if you've had this problem in the past, but on Sierra I had this annoying wake-from-sleep lag even on a full 2017 iMac Core i5 SSD-based system. It was up to something like 7 seconds, so some of you may think it's not a big deal. That may be true overall but nonetheless the lag still seemed like an eternity by SSD standards.
This Sierra system was a transfer from previous 2010 iMac. But because I had the lag, I tried re-installing Sierra via recovery mode over the existing Sierra install (maintaining the existing data), but the lag persisted.
However, now that I've upgraded to High Sierra (on APFS), that lag has disappeared. Now it's up to just a couple of seconds, which is more than reasonable.
I wonder what did it, but strangely enough, other than HEVC/HEIF support, this is the single-most important upgrade for me for High Sierra. Note that I did NOT do a clean install of High Sierra. It was just an upgrade over my existing Sierra install.
This Sierra system was a transfer from previous 2010 iMac. But because I had the lag, I tried re-installing Sierra via recovery mode over the existing Sierra install (maintaining the existing data), but the lag persisted.
However, now that I've upgraded to High Sierra (on APFS), that lag has disappeared. Now it's up to just a couple of seconds, which is more than reasonable.
I wonder what did it, but strangely enough, other than HEVC/HEIF support, this is the single-most important upgrade for me for High Sierra. Note that I did NOT do a clean install of High Sierra. It was just an upgrade over my existing Sierra install.
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