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macrumors 68000
Original poster
Mar 6, 2008
Hello Everyone!

For some reason I'm getting very poor SSD performance with my Macbook 12" 2015, It's only about 2 months old. The speeds were fairly decent before, not sure if It's because of the storage used up.

This is my first time using PCI based storage and I was hoping it'd sustain close to the speeds I was getting when I first bought the Macbook. According to the System Profiler Trim is enabled.


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macrumors 6502
Oct 29, 2014
Oregon North Coast
I would also suspect the SSD is too close to full, especially given the very poor write speed. I just ran this test on a Late 2008 Unibody MacBook (2.0 GHz) with a 250 GB Crucial MX200 SSD (170 GB free) and I was consistently getting write speeds more than double what you posted (overall, about 200 writing and 265 reading) -- and that's with a machine more than seven years old. If you can, copy/backup some of your files and lesser used apps to an external drive, free up some space and try it again.


macrumors 68000
Original poster
Mar 6, 2008
Screen Shot 2016-04-24 at 11.54.54 PM.png

I have about 20GB free.. I suspected it was due to the storage used up, but I personally haven't experience this on a traditional SSD. The performance it wasn't as drastic..


macrumors member
Jul 28, 2008
18gb is shortt, but afaik it shouldn't drop that low in perf.

What i'd do in any case
- Make sure everything is bacuped. TM or whatever.
- Free up some decent space (say at least 10%, the more the better, at least to locate the problem), copy files to external drive, etc...

Than try in no particular order
- reset PRAM / NVRAM
- See disk status in disk utility, try the SOS (maybe)
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