Samsung EVO 860 1TB really slow in testing
I bought a Samsung EVO 860 1tb SSD last fall to use in my MacBookPro (15”, late 2011), which is now dying, and now my iMac (27”, late 2012) needs a new HD, so I thought I would take this drive out of the MBP and use it in the iMac. I have the iFixit kit for iMac SSD installation, so the last step is confirming which SSD to use.
Before installing, I wanted to do some testing using Black Magic Disk Speed Test, here are the results:
iMac Fusion Drive (HDD+SSD):
Write: 150-200mb/s
Read: 250-400mb/s
Samsung 860 EVO:
Write: 30-50mb/s
Read: 220mb/s
So my question is, what’s going on here? It makes no sense at all that the fusion drive tests results are beating the pants off the EVO, which is giving worse results than just about any HD I can recall testing. I did test the speed via Thunderbolt 1 using Target Disk Mode, but also got similar results directly on the MBP that houses the EVO. The SSD is pretty full, would that have a drastic affect on the speed? Is this thing just bad?
Thanks in advance for any help!
좋은 질문입니까?
How are you connecting the drive via the USB3 connection or via a Thunderbolt drive case?
If you used a SATA to USB adapter or drive case you are bing limited to the USB connection.
Dan 의
Hey Dan, I'm connecting the two machines with a Thunderbolt cable
Adam Milton 의
The chaining you have done is too complex for any true measure of performance.
You have two systems PCH logic which has to be navigated when using Target Disk Mode (being the faster) and if you are using a networked connection via Thunderbolt you have the systems CPU's involved which then adds more delay into the measure.
Dan 의
@danj That's a great point, I also did testing directly on the MBP, and the results typically start off better on the first test (W: 70mb/s, R: 330mb/s), but then after a few more tests, the results level off at W: 30mb/s, R: 300mb/s. The read is faster, but the write is the same, or worse when testing directly on the MBP.
The MBP has a bad GPU, so I can run the MBP for short periods of time before it eventually crashes.
Adam Milton 의