eva_the_curious wrote:
Hello,
My iMac (2017) is running very slow.
When the problem first started I tried troubleshooting with the help of Apple Support. I did an OS reinstall and used Disc Utility to erase discs according to Apple support notes, but I don't think I've done it right because now it runs even slower!
Please help! :-)
From EtreCheck report:
Low performance: EtreCheck report took an unusually long time to run
External drives and performanceThere are external drives connected that could be affecting performance.
Limited permissionsMore information may be available with Full Disk Access.
The full report is here:
<EtreCheck Report.log>
Your report shows the iMac 2017 Fusion Drive configuration (128 GB SSD + 2 TB HDD [mechanical drive] @ 7200rpm). Normally these Fusion Drives are the high end configuration that show 500+ MB/s performance. Yet yours shows much worse:
Write speed: 106 MB/s
Read speed: 141 MB/s
In fact those numbers are typical of a mechanical HDD alone, with no boost from an SSD. I also don't see the drive explicitly identified as a Fusion Drive in the Etrecheck Report, which it should be. Which makes me think that the Fusion Drive is broken now or "split," or possibly the SSD piece has failed.
Reconstructing the Fusion Drive is something for which online instructions have been provided in these Discussions and elsewhere, but I have never owned a Fusion Drive so I don't claim to be the right person to guide you. If it were me, I would take the Mac to an Apple Authorized Service Provider (AASP), these are third party shops that Apple certifies. I think your Mac is too old for an Apple Store to service, but AASPs will often take this type of job on. I would ask them to verify that both Fusion Drive components are healthy, and then have them reconstruct the proper Fusion Drive configuration. You should have 2 good backups of everything before embarking on anything like this. Alternatively, Apple Support (via phone or chat) can walk you through this Fusion Drive fix but it isn't simple for people not used to this type of thing.
I am not 100% sure that your Fusion Drive has split but the circumstantial evidence indicates that this very well may have happened.
P.S. Here is a link regarding fixing a split Fusion Drive, if that applies to you:
How to fix a split Fusion Drive - Apple Support
