Weird performance issue

theukmoog · 5 Nov 2024 at 13:36

My desktop PC has a 500GB Samsung 870 SSD as a boot drive, which I backup by imaging to two SSDs in a USB dock twice a week.

The first image, to another 500GB Samsung 870 SSD takes 7mins.
The second image, to a 500GB Fanxiang S101 SSD, takes 30mins!

I assumed this was just down to the Fanxiang being a much cheaper drive than the Samsung but, for backup images, I could live with it.

I bought a 2TB Crucial BX500 for my laptop at the weekend and decided to check it was ok in my Desktop USB dock and took the opportunity to benchmark all 3 drives.

I was very surprised to see that all 3 benchmarked with very similar numbers (all in the USB3 dock)...

500GB Samsung 870

500GB Fanxiang S101

2TB Crucial BX500

So why does that Fanxiang take 30mins to make an image (using Macrium) whilst the Samsung and Crucial both take 7mins?!?!

theukmoog · 5 Nov 2024 at 14:13

All 3 benchmarks and the images are always done in the same slot of the USB dock.
I've had this setup for 18months and it has performed like this from day 1 but, as it's just my backup images, I've not looked into it any deeper.

The image files are currently around 150GB each, so each drive has my last 3 images on.

In my mind, it indicates something lacking in the Crystal benchmarking, as given the 3 results above, you would expect very similar real world performance.
It has also persuaded me to stick to the big, well-known brands for my storage requirements in the future

I did verify all of the images and they are all ok, according to Macrium, so I'm happy that my backup regime is secure, just wondered about the vastly different performances.

theukmoog · 5 Nov 2024 at 14:41

Thanks for such comprehensive responses... took me out of my comfort zone on how SSDs work!

I guess you wouldn't really see such a performance dip if the drive was being used 'normally' and not just for writing out a big backup image.

theukmoog · 6 Nov 2024 at 20:12

I received a 500GB Crucial BX500 today, as I plan to move to Win11 on my desktop and prefer to keep the old SSD as a working backup and start with a new Boot SSD.

The 500GB Crucial BX500 benchmarked much like its 2TB brother...

but when used for writing a backup image to, it was woefully slow again, taking 27mins!

The packaging was identical for the 2 drives and the 500GB even quotes faster speeds of "up to 550MB/s" on the box (2TB says "up to 540MB/s").

This experience has certainly opened my eyes on the SSD front!