MacBook Pro - SSD Deterioration!

marc5000 · August 17, 2015

Ok - so a bit of a controversial topic, however I use a MacBook Pro when I'm travelling around and at home (don't kill me(!))

I purchased this MacBook Pro when the Retina display was first released (oh the joy). It was great, and the performance was killer.

Fast forward three years to today and the Book is struggling - especially in the SSD department.

Write performance on my drive has gotten worse. Even after running trim in via 'Disk Utility' - and really making sure the drive isn't super full (about 80%), I still can't work out why drive performance has really depreciated like this?!

- Write: 80MB/s (should be 400ish!)

- Read: 440MB/s (seems fine)

Here is a video of what I mean, this is my desktop running Speed Test;

Could the drive actually be dying? Replacement?

Another speed test shows the write performance jumping, quite drastically! I don't know what to make with these figures.

ZetZet · August 17, 2015

80% full is full for ssd's.

marc5000 · August 17, 2015

ZetZet - thanks.

Yep, you were right. Turns out that OSX doesn't include local 'Time Machine' backup data allocated against the used hard drive space.

Basically means it wasn't counting space it used for local backup - in the hope that you would overwrite this anyway. Stupid. This meant that the drive was fuller than it should have been.

sudo tmutil disablelocal- to disable local cached Time Machine backups. This saved me 70GB off the SSD!!

Back to reasonable SATA SSD speeds :lol:

No fluctuating graphs..