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1. BLACKMAGIC DISK SPEED TEST OF MACBOOK PRO 2012 256 SSD DOWNLOAD
2. BLACKMAGIC DISK SPEED TEST OF MACBOOK PRO 2012 256 SSD MAC

4096 blocks (mind the count to get the same number of bytes): $ dd if=/dev/zero of=test count=800000Ĥ09600000 bytes transferred in 2.173086 secs (188,487,708 bytes/sec) So let's compare the default 512 byte blocks vs. On the shell, you can determine your SSD's block size via diskutil info /, e.g.: $ diskutil info / | grep Block It's using a block size of 512 bytes by default, which on an SSD is far from optimal.

BLACKMAGIC DISK SPEED TEST OF MACBOOK PRO 2012 256 SSD MAC

mac mini 256gb internal relatively full: write 1.5GB/s, read 0.75GB/s.Per darkdust's answer below, here are versions with 4096 block size: I also checked whether /dev/zero has special tricks (through comparison with /dev/random), but the modest deterioration on all drives suggests that my dd really does write zeros to ssd. PS: I compared this to performance on an external USB3 sandisk SSD 2TB, where I get about twice the write performance and about half the read performance. Is this the number I should be expecting? (I know that there is overhead I believe on an SSD, file fragmentation is no longer the issue it once used to be, however.) If you only have one drive (if you’re not sure, then you probably just have one), all you have to do is hit START since the program only has one window.

BLACKMAGIC DISK SPEED TEST OF MACBOOK PRO 2012 256 SSD DOWNLOAD

(commas added by me): % time dd if=/dev/zero of=1 count=10000000ĥ120000000 bytes transferred in 20.313020 secs (252,055,086 bytes/sec)Īt 252MB/s, this is not exactly endearing. First, you’ll need to download BlackMagic from the Mac App Store (it’s completely free). I am not interested in synthetic raw disk performance, but in performance on the APFS file system. It is not a fresh disk-I now have only about 30GB remaining.