Testing TRIM

A firmware update gives you TRIM support, but we should probably test to make sure it's actually working.

First up, the Intel X25-M G2 with the TRIM firmware. I ran a 4KB random write test across the entire 80GB LBA space for five minutes. I ran the test again afterwards and recorded the average transfer rate for each run:

4KB Random Write, IOQ=16 Run 1 Run 2
Intel X25-M 80GB TRIM Firmware 37.9 MB/s 13.8 MB/s


As expected, performance goes down as the drive fills up. The second run is much slower than the first.

Now look at the two runs if we format the drive in between. The format under Windows 7 triggers a TRIM of all invalid data, meaning all the jibberish we generated in the first run is gone and the second run now runs at full speed:

4KB Random Write, IOQ=16 Run 1 Run 2 after Format
Intel X25-M 80GB TRIM Firmware 37.9 MB/s 38.0 MB/s


Obviously you don’t usually write a bunch of garbage to your drive then format and repeat, but we’re trying to confirm that TRIM works here; it does. Windows 7 will actually take noticeably longer to format a drive that supports TRIM and has data on it. It still completes in less than 30 seconds on these SSDs, but it's a lot longer than the few seconds it used to take before TRIM.

This confirms that TRIM works on a format, but what about if you delete a partition? To find out I created a partition on my X25-M G2, filled it with data, deleted the partition and ran my 4KB random write test across all LBAs. If deleting a partition forces TRIM I should see new-performance out of the G2:

4KB Random Write, IOQ=16 Run 1 Run 2 after Deleting Partition
Intel X25-M 80GB TRIM Firmware 37.9 MB/s 17.9 MB/s


Performance drop. Formatting a partition causes the contents to be TRIMed, but just deleting a partition doesn’t. This means if you accidentally delete a partition you can still retrieve your data, however there’s no way to go back from a format.

What about file deletion? I performed the same test. Created a partition, filled it with garbage but then deleted the garbage before deleting the partition and running my 4KB random write test. Deleting data should force a TRIM:

4KB Random Write, IOQ=16 Run 1 Run 2 after Deleting All Files
Intel X25-M 80GB TRIM Firmware 37.9 MB/s 40.4 MB/s


Indeed it does. You no longer have to worry about performance dropping over time. When you delete a file it’ll eventually be nixed on the SSD as well. Below we have the actions that will force a TRIM of data under Windows 7:

Windows 7 File Delete Partition Format Partition Delete
TRIM? Yes Yes No


Formatting your drive now actually does something. You no longer have to boot to DOS and secure erase your SSD before installing Windows, just quick format the partition before installing Windows 7.

I performed the same tests on an Indilinx MLC based SSD, this time a SuperTalent UltraDrive GX with the 1819 TRIM-enabled firmware. The results were identical:

4KB Random Write, IOQ=16 Run 1 Run 2 After Format After File Delete
SuperTalent (Indilinx) UltraDrive GX TRIM Firmware v1819 17.8 MB/s 14.1 MB/s 17.8 MB/s 17.8 MB/s


We have TRIM working on both Indilinx (from SuperTalent/OCZ) and Intel drives. Sweet.

Index Wipe When You Can’t TRIM


View All Comments

  • Anand Lal Shimpi - Monday, October 26, 2009 - link

    Personally my pick is still the X25-M, it's had a better track record than any of the other controller makers. The problem for Intel is that Indilinx performance and feature set have both gotten a lot better.

    You now get TRIM, reliable performance, competitive pricing and generally everything but a super dynamic controller that's constantly trying to maximize performance. Depending on the usage scenario though, the latter may not matter as much (see my Photoshop results from the last review or the heavy trace results from this review).

    My position hasn't really changed, just highlighting the importance of the issue so that hopefully Intel's value SSDs next year aren't just rebadged G2s :)

    Take care,
  • 7Enigma - Monday, October 26, 2009 - link

    I think his previous review is consistent with this one. His ultimate recommendation between Intel and Indlinx drives has remained unchanged. That is, they are close enough that the size differences should be the decider for a potential buyer.

    As it stands, in most normal usage scenarios the statement from his last article still applies. There are very few times where you are going to be constantly tapping the 80MB/s barrier. More often you will be limited by the other SSD's lower random write speeds.

    What his own benchmark can show is that in uncommon circumstances you can sway the bar back towards parity between the brands. I would argue, however, that the "heavy" usage scenario is not a practical one for an SSD. Just read his description again and look for all of the places the average user would NOT be putting that data onto an SSD:

    In this test we have Microsoft Security Essentials running in the background with real time virus scanning enabled. We also perform a quick scan in the middle of the test. Firefox, Outlook, Excel, Word and Powerpoint are all used the same as they were in the light test. We add Photoshop CS4 to the mix, opening a bunch of 12MP images, editing them, then saving them as highly compressed JPGs for web publishing. Windows 7’s picture viewer is used to view a bunch of pictures on the hard drive. We use 7-zip to create and extract .7z archives. Downloading is also prominently featured in our heavy test; we download large files from the Internet during portions of the benchmark, as well as use uTorrent to grab a couple of torrents. Some of the applications in use are installed during the benchmark, Windows updates are also installed. Towards the end of the test we launch World of Warcraft, play for a few minutes, then delete the folder. This test also takes into account all of the disk accesses that happen while the OS is booting.

    The benchmark is 22 minutes long and it consists of 128,895 read operations and 72,411 write operations.

    How many people are going to be opening photoshop pictures FROM the SSD and saving them TO the SSD? Same goes with Windows Picture Viewer. Most people will have their pics on a standard large mechanical HD which makes this a moot point. Downloading large files from the net? Not a chance that would be going to my SSD! Bottom line is this is a great HELL test, but nowhere close to real-world usage.

    The light-usage probably fits 90% of people 90% of the time (completely made up statistic).

    With all of that said, I wish Intel's 80gig drive had closer sequencial write performance as the Indilinx drives, as it would make the decision a complete no-brainer. Looking at all the data, and planning on buying a ~$250 drive this holiday season has me very likely picking up an 80gig Intel as for me the price is about as steep as I'm willing to go for essentially a boot drive, with performance that for the majority of the time is at the top of the pack. It would be WAYYYY more difficult to decide if both Intel/Indilinx had the same drive sizes but fortunately we don't have to worry about that (at least for now....)
  • tynopik - Monday, October 26, 2009 - link

    on page 7, all the graphs have two lines labelled 'Intel X25-M G2 80GB (MLC) TRIM' Reply
  • 7Enigma - Monday, October 26, 2009 - link


    You have listed the 80gig Intel MLC drive twice in each chart. I'm assuming one of them shouldn't say (TRIM)?

    Other than that, GREAT article! Those Kingston drives look to be the PERFECT inexpensive replacement for netbooks/cheaper laptops as the performance is vastly superior to cheap mechanical HD's.
  • Anand Lal Shimpi - Monday, October 26, 2009 - link

    That second 80GB MLC drive was actually a second set of results that didn't get pulled out. I've trimmed em out :)

    Take care,
  • fic2 - Monday, October 26, 2009 - link

    "The G1 is more resillient (SIC) than the G2 when it comes to performance degradation over time since it doesn't have TRIM."

    Is it just me or does this sentence make no sense? I thought the whole purpose of TRIM was to make the SSD more resilient to performance degradation. Seems like it should be:
    "The G1 is less resilient..."
  • klil - Monday, October 26, 2009 - link

    The G1 is LESS susceptible to degradation than the G2, Intel compensates this by enabling TRIM on the G2. Reply
  • Anand Lal Shimpi - Monday, October 26, 2009 - link

    Correct, my apologies for the confusing wording :)

    Take care,
  • edzieba - Monday, October 26, 2009 - link

    "None of the other Indilinx manufacturers have Windows 7 TRIM support yet."
    Crucial has the TRIM firmware (1819) available for download for their m225 series SSDs.
  • TheWickerMan - Monday, October 26, 2009 - link

    I was just going to post that, but you beat me to it. Here's the link for anyone else interested: http://www.crucial.com/support/firmware.aspx">http://www.crucial.com/support/firmware.aspx Reply

Log in

Don't have an account? Sign up now