Again - Late2015 iMac very slow

Hi there!

Thank you for linking your previous thread! I've checked both reports, and it appears the BX500 SSD is becoming too taxed under heavy usage. As explained by a fellow ASC user here, HWTech, the BX500 is an SSD that can easily become slower than a hard disk under moderate to heavy usage. The "burst" of performance you're seeing is likely when the SSD is still running smoothly, but after a while of operation, the BX500 cannot recover quickly enough for sustained performance. 

These disk performance scores support that. Notice the drop in read and write performance, but also the timed out warning for the file system. EtreCheck also reported "SSD too slow - SSD is showing poor performance" in the poor performance report. 

From "Report excellent"

Performance:

System Load: 8.52 (1 min ago) 16.83 (5 min ago) 9.07 (15 min ago)

Nominal I/O usage: 0.44 MB/s

File system: 14.96 seconds

Write speed: 443 MB/s

Read speed: 526 MB/s

From "Report poor"

Performance:

System Load: 2.66 (1 min ago) 3.82 (5 min ago) 5.46 (15 min ago)

Nominal I/O usage: 0.06 MB/s

File system: 126.24 seconds (timed out)

Write speed: 209 MB/s

Read speed: 199 MB/s

I also see heavy memory usage in the second report. With the BX500 being slower, the caching and swap of memory to the SSD can cause the Mac to slow down even more. A 8GB memory kit to bring your Mac to 32GB total (replacing the two 4GB memory modules, and having four 8GB modules total) can help with that: 8GB OWC Memory Upgrade Kit - OWC. Then, you can reference Install memory in an iMac - Apple Support. Since it sounds like you use virtualization software, more memory is always better!

Moving forward, I'd strongly suggest an external SSD boot/startup disk solution, connected through the USB 3 ports on your Mac. That way, you can re-use the external drive when you upgrade to a new Mac and not have to open the Mac. It's important to use a high-quality external SSD that can perform well and show improvement over the BX500.

In your case, I think looking at options from Other World Computing (OWC) would be wise. The reason being OWC tells you the actual drive/SSD used in each external enclosure, so you can research the drive itself and verify that it is a good option. The 1.0TB OWC Envoy Pro Elektron - OWC (with the required 0.6M (24") OWC USB-C Cable With Tethered USB-C to USB-A Adapter - OWC) should be a great option for you. 

The LaCie Rugged Mini SSD 1TB - Apple from the Apple Store, with an adapter cable, such as the Belkin 3.1 USB-A to USB-C Cable, is also a good option.

Then, you can follow this guide: Use an external SSD as your startup disk … - Apple Community.

Hope this helps!

-Jack

I would un-install Surfshark, Parallels & Adobe - see if it makes enough of a difference. If not, replace your Mac with new - your iMac is officially obsolete and close to packing up.

Whatever you do, keep Surfshark and any other 3rd party virus/malware/performance apps including Etre & Malware safely away - usually not up to any good and best avoided. Good luck!

HerzerSkerzer wrote:

So I see that probably I chose the wrong SSD to swap my old fusion drive.

Yea' the Crucial BX500 SSD are notorious for iffy-ness and slowing down over time.

I'd love to use an internal SSD, if possible. I don't mind opening the iMac again, but I prefer that rather than having external stuff on the desk.

First try enabling Trim on the Crucial BX500 and then test it out for a few days.

https://www.akitio.com/faq/377-how-to-enable-trim-on-macos

If that doesn't fix, replace the BX500 with a Crucial MX500, a WD Blue or a PNY CS900 SSD.

FWIW I have used PNY SSDs in more than a dozen older Mac's over the years and all are still preforming as expected.

https://www.amazon.com/PNY-CS900-Internal-Solid-State/dp/B07Y5VDNT9/ref=sr_1_3?

The current 24GB installed appears to be more than enough for your current usage.

What you need to do next, is completely expel SurfShark and MacKeeper from your system as per the developers directions.

Then perhaps use Safari or FireFox instead of Chrome which is a huge resource hog.