The program then tells you what kind of uncompressed video that drive will be able to handle and allows you to save the results as a screenshot.Īs you can see from the image above, my magnetic hard drive-equipped MacBook Pro isn't going to win any speed awards. Disk Speed Test writes large chunks of data to your chosen disk and then reads that data, giving you a real-world read/write speed in MB/s. Disk Speed Test from Blackmagic will give you a quick, straightforward answer. ioMeter is the best open source benchmarker out there however they don't fully support OSX, just the worker engine binaries - so iometer itself would have to run on a separate machine.You've got a shiny new SSD-equipped machine, but you're wondering just how fast that SSD really is. during regular multi application usage of the OS. iow - this is as fast as it gets and in no way indicative of how your drive performs when ~30-50% of its reads and writes are random - i.e. One more thing to add and I don't know if was already mentioned or not tl:dr - this is a sequential test only. ~> time dd if=/dev/zero bs=2048k of=tstfile count=1024 2>&1 | awk '/sec/ 'Īaaah much more like it. The system has 16GB of ram, a 3.5 GHz i7 and 512 GB PCI-e (]> 01:19:24 Allow me to demo this on my snazzy new iMac with the PCI-e drive. This prevents caching and artificially inflated read speeds. One additional thing that might be worth mentioning.your test file (tstfile) should be larger than the amount of physical ram. The commands above will give you average speeds, whereas Activity Monitor shows the speed in real time, as well as peak speeds.See the comments below for what may be a better approach.] This shows that I have a peak read speed of 137 MB/sec, and a peak write speed of 151 MB/sec (an SSD in a Mac mini). You can run the above commands while watching the information in Activity Monitor, and skip making the conversions. FWIW, my new Thunderbolt drive has throughput of about 100 MB/sec. Copy a large file from one disk to another to see how fast it can go. Open Activity Monitor (in /Applications/Utilities), click on the Disk Activity tab at the bottom of the window, then look at the Data read/sec and Data written/sec numbers. To test read speed: dd if=tstfile bs=1024k of=/dev/null count=1024[ kirkmc adds: While we're on the subject, here's an easy way to test data throughput from one disk to another. Google search for '519131791 bytes/s in megabytes/s').

To test write speed: time dd if=/dev/zero bs=1024k of=tstfile count=1024In the output, you should look for something that looks like 'bytes transferred in 16.546732 secs (519131791 bytes/sec).' Copy and paste the bytes/sec speed into Google to convert to MB/s (e.g.

You can benchmark the speed of your SSD or hard disk using a few simple Terminal commands.

Mac disk speed test