Every time I look at HDD vs SSD tests they always do the same thing a boot up test. I have always wanted to know what the swap file performance was like between the 2.
When you load a lot of webpages or apps your memory fills up and OSX starts using your hard disk as virtual memory (a swapfile/pagefile). In fact annoyingly this starts happening way before you run out of RAM. At this point your performance is limited by how fast your hard drive can access and write to its swap file.
Test:
System : MBP Late 2008 2.8ghz Core 2 Duo, 4GB RAM ddr3, SATA 2 Interface
250GB WD Scoprio 5400rpm
256GB Crucial M4 SSD
Load up Safari, Opera, Chrome, Firefox with
50 webpages per browser spread across 10 windows.
Results:
HDD
loaded safari with 50 pages =
fine
loaded opera with another 50 pages =
fine, however safari lost all its pages and requested a force reload all pages
loaded chrome with another 50 pages =
right click menu response now delayed by 3-5 seconds. Browser menus starting to beach-ball on selection. Spaces response now delayed by 5-10 seconds, expose response delayed by 1-3 seconds. Animations now juddering.
loaded firefox with another 50 pages =
delays and system response become too severe to be usable. Test terminated before all windows open.
SSD
loaded safari with 50 pages =
fine
loaded opera with another 50 pages =
fine
loaded chrome with another 50 pages =
fine
loaded firefox with another 50 pages =
fine (very mild judder to spaces animation but smooth again after 10 seconds)
Analysis
Looking at activity monitor you can see that the HDD is swapping in/out at 0.5-1.5MB/s the SSD is swapping out at between 2-25MB/s sometimes as high as 75MB/s. The test required a total of 10GB of data to be read from the HD and SSD swap.
Conclusion
An SSD does significantly reduce beacd-balling and instability caused by heavy multitasking. These same results can be replicated by light multitasking over time. As OSX uses the swap file even when memory is available the swap file seems to be used more and more until you restart and wipe the slate clean again. An SSD seems to keep you going even when it is being used in place of memory. If this kind of performance is important to you, look to the Random read/ write performance on benchmarks (especially 4k) when buying not the max sequential.
When you load a lot of webpages or apps your memory fills up and OSX starts using your hard disk as virtual memory (a swapfile/pagefile). In fact annoyingly this starts happening way before you run out of RAM. At this point your performance is limited by how fast your hard drive can access and write to its swap file.
Test:
System : MBP Late 2008 2.8ghz Core 2 Duo, 4GB RAM ddr3, SATA 2 Interface
250GB WD Scoprio 5400rpm
256GB Crucial M4 SSD
Load up Safari, Opera, Chrome, Firefox with
50 webpages per browser spread across 10 windows.
Results:
HDD
loaded safari with 50 pages =
fine
loaded opera with another 50 pages =
fine, however safari lost all its pages and requested a force reload all pages
loaded chrome with another 50 pages =
right click menu response now delayed by 3-5 seconds. Browser menus starting to beach-ball on selection. Spaces response now delayed by 5-10 seconds, expose response delayed by 1-3 seconds. Animations now juddering.
loaded firefox with another 50 pages =
delays and system response become too severe to be usable. Test terminated before all windows open.
SSD
loaded safari with 50 pages =
fine
loaded opera with another 50 pages =
fine
loaded chrome with another 50 pages =
fine
loaded firefox with another 50 pages =
fine (very mild judder to spaces animation but smooth again after 10 seconds)
Analysis
Looking at activity monitor you can see that the HDD is swapping in/out at 0.5-1.5MB/s the SSD is swapping out at between 2-25MB/s sometimes as high as 75MB/s. The test required a total of 10GB of data to be read from the HD and SSD swap.
Conclusion
An SSD does significantly reduce beacd-balling and instability caused by heavy multitasking. These same results can be replicated by light multitasking over time. As OSX uses the swap file even when memory is available the swap file seems to be used more and more until you restart and wipe the slate clean again. An SSD seems to keep you going even when it is being used in place of memory. If this kind of performance is important to you, look to the Random read/ write performance on benchmarks (especially 4k) when buying not the max sequential.