I recently started getting performance issues with my MBP while running apps like Xcode and Eclipse. A quick diagnostic of the system showed that it thrashed over 458k times.

Vendor Specific SMART Attributes with Thresholds:
  1 Raw_Read_Error_Rate     0x000b   095   095   062    Pre-fail  Always       -       458757

I just ordered a SSD to replace the HDD, will this help solve the problem, and also how do I get OSX back onto the computer if I replace the HDD and the new SSD is empty?

2 Answers 2


Put it in an external caddy, USB etc, then use something like Carbon Copy Cloner to duplicate it.

It will then be bootable when you swap.


This RAW value means nothing to you disregard it. Here is on understanding SMART attributes.

From there:

PLEASE completely ignore the RAW_VALUE number! Only Seagates report the raw value, which yes, does appear to be the number of raw read errors, but should be ignored, completely. All other drives have raw read errors too, but do not report them, leaving this value as zero only. To repeat, Seagates are not worse than other drives because they appear to have raw read errors, rather they are the only one to report the number. I suspect that others do not report the number to avoid a lot of confusion, and questions for their tech support people. Seagate leaves those of us who provide tech support the job of answering the constant questions about this number. Hopefully now that you understand this, you will never bother a kind IT person with questions about the Raw_Read_Error_Rate RAW_VALUE again?

Regarding getting OS X on computer you can either clone your existing install (like mentioned before), start with Internet Recovery (pressing cmd + r) or prepare bootable USB key with installer with Diskmaker X utility or manually

System on SSD for sure be a lot faster than on HDD

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