Stopwatch based real world testing
Real world tests are the best way to compare how an SSD will perform in the real world, as they give a clear guide as to what SSDs are weak or perform well at. For example, an SSD that may boot the OS in seconds may struggle against a hard disk when faced with a software installation or update. Some SSDs may struggle with multitasking and so on.
Some reviewers include timings of Windows starting up, applications being launched and file copying. For the best tests, have a look for reviews that show timings of software installations as well as comparisons against a hard disk with spinning platters such as the WD Raptor, as these tasks can be more tedious than any synthetic test and often reveal the weaknesses of an SSD. At this time of writing, the only review websites I’m aware of that conduct software installation tests are MyCE, Legit Reviews and Hardware Heaven, mainly due to the time involved in preparing for each test, not to mention conducting it, such as timing the installation of Windows 7 Service Pack 1.
Of course there are drawbacks as well. For example, the timings are largely affected by the operating system, CPU speed, amount of RAM, drivers and so on, so comparisons can only be compared between drives conducted by the same reviewer and the same test PC. Usually most reviewers include a traditional hard disk in their tests, which can be used a reference to give an idea of how much better the SSD performs.
Script based real world testing
Some websites have their real world tests set up by a script, where all the application launches, file copy timings, etc. are conducted and timed automatically by the script. The advantage here is that more simultaneous tasks can be carried out such as to simulate a terminal server with a large number of users logged on and the timings are more accurate, reducing or eliminating the need to repeat tests to get an average or where the user forgot to start/stop the stopwatch. The script can also carry out more awkward tests such as loading photos in editing software, carrying out tasks such as sharpening, cropping, etc. and saving them.
A drawback with script testing is that some important tests such as software installation and especially Windows updates and service pack installations cannot be carried out by script easily, thus some SSD reviewers carry out script tests in addition to stopwatch based testing.
Note that some websites which claim to do replay real world tests on a drive are simply playing back recorded IO traces from real world tests they conducted earlier. In this case, these tests are not real world, but instead a real world simulation as discussed on the previous page, where the SSD may behave differently depending on how the IO trace is played back.
TRIM testing
This test involves hammering the SSD with a lengthy period of random write operations such that its performance becomes crippled due to its free space all being used up. The reviewer then measures its performance such as with AS SSD, CrystalDiskMark or IOMeter to show how it compares with when it was in its clean new state.
Next, the reviewer leaves the SSD idle over several hours (usually overnight) and finally repeats the tests to show how much the performance has recovered with the SSD’s background garbage collection. Basically, this gives an idea of the worst case scenario for the SSD if the user is carrying out an extensive amount of writing to the SSD, such as if the SSD is used in the file server of a busy photography or music studio.
Power consumption
If the SSD is to be used in a laptop or Netbook, it is useful to find out its power consumption to give an idea of how it will affect battery life. Generally most modern SSDs consume a tiny fraction of what energy a hard disk typically consumes, but this figure is still useful for laptop/netbook users looking to get every additional minute of battery time.
