Random Read/Write Performance

Arguably much more important to any PC user than sequential read/write performance is random access performance. It's not often that you're writing large files sequentially to your disk, but you do encounter tons of small file reads/writes as you use your PC.

To measure random read/write performance I created an iometer script that peppered the drive with random requests, with an IO queue depth of 3 (to add some multitasking spice to the test). The write test was performed over an 8GB range on the drive, while the read test was performed across the whole drive. I ran the test for 3 minutes.

The three hard drives all posted scores below 1MB/s and thus aren't visible on our graph above. This is where SSDs shine and no hard drive, regardless of how many you RAID together, can come close.

The two Intel drives top the charts and maintain a huge lead. The OCZ Vertex actually beats out the more expensive (and unreleased) Summit drive with a respectable 32MB/s transfer rate here. Note that the Vertex is also faster than last year's Samsung SLC drive that everyone was selling for $1000. Even the JMicron drives do just fine here.

If we look at latency instead of transfer rate it helps put things in perspective:

Read latencies for hard drives have always been measured in several ms, but every single SSD here manages to complete random reads in less than 1ms under load.

Random write speed is where we can thin the SSD flock:

Only the Intel drives and to an extent, the OCZ Vertex, post numbers visible on this scale. Let's go to a table to see everything in greater detail:

4KB Random Write Speed  
Intel X25-E 31.7 MB/s
Intel X25-M 23.1 MB/s
JMicron JMF602B MLC 0.02 MB/s
JMicron JMF602Bx2 MLC 0.03 MB/s
OCZ Summit 0.77 MB/s
OCZ Vertex 2.41 MB/s
Samsung SLC 0.53 MB/s
Seagate Momentus 5400.6 0.81 MB/s
Western Digital Caviar SE16 1.26 MB/s
Western Digital VelociRaptor 1.63 MB/s

Every single drive other than the Intel X25-E, X25-M and OCZ's Vertex is slower than the 2.5" Seagate Momentus 5400.6 hard drive in this test. The Vertex, thanks to OCZ's tweaks, is now 48% faster than the VelociRaptor.

The Intel drives are of course architected for the type of performance needed on a desktop/notebook and thus they deliver very high random write performance.

Random write performance is merely one corner of the performance world. A drive needs good sequential read, sequential write, random read and random write performance. The fatal mistake is that most vendors ignore random write performance and simply try to post the best sequential read/write speeds; doing so simply produces a drive that's undesirable.

While the Vertex is slower than Intel's X25-M, it's also about half the price per GB. And note that the Vertex is still 48% faster than the VelociRaptor here, and multiple times faster in the other tests.

Sequential Read/Write Performance SYSMark 2007
POST A COMMENT

377 Comments

View All Comments

  • KadensDad - Tuesday, October 27, 2009 - link

    How do these drives fail? I have heard that they will just suddenly die, no more writes or reads possible. What I would like to know is what happens when it dies? Do you lose all data? Just can't write anymore? How does the OS respond? Any early warnings? What about e.g. CRC? How does possibility of data corruption compare to traditional SSD? What about RAID? Since the drives are electrical, not mechanical, this reduces the number of failure vectors and environmental concerns (e.g., ambient temperature over lifetime of the drive). Won't SSDs therefore fail closer together in time in a RAID configuration? This reduces the window of opportunity for fixing an array and also decreases the applicability of RAID, however marginal.
    Reply
  • Dewend - Friday, March 04, 2016 - link

    My partner and i also were seated for lunch, whenever i mentioned to her that I read a script each and every morning newspaper, therefore i chosen to do a little research. Thankfully, I stumbled upon this website, which helped me discover why people consider even thinking about this. http://followersteam.com Reply
  • Askipod - Thursday, November 17, 2016 - link

    This is cool! Your website is great Hey Your information is astounding!! I will recommend it to my brother and anybody that could be attracted to this topic. Reply
  • Askipod - Thursday, November 17, 2016 - link

    WOW. I am very glad to join this comunity and enjoy your article. Your article shared me so interesting information here, looking forward to your update. http://www.nasze.media.pl/pisanie-tekstow-jako-spo... Reply
  • echtgeld - Monday, January 16, 2017 - link

    http://echtgeld-casino.net/ - beste online casinos site Reply
  • SecXploded - Saturday, February 25, 2017 - link

    Exactly. you’re very kind of us about comment - <a href="http://www.nohumanverification.com">www.no... Reply
  • BMNify - Monday, August 21, 2017 - link

    https://hack-crack-games.fr/ - Hack jeux mobile android et ios Reply
  • rahul12 - Thursday, September 14, 2017 - link

    thanks for you suggestion friend http://hdgametricks.com/ Reply
  • SecXploded - Saturday, February 25, 2017 - link

    Exactly. you’re very kind of us about comment - www.nohumanverification.com Reply
  • SecXploded - Saturday, February 25, 2017 - link

    Exactly. you’re very kind of us about comment - http://www.nohumanverification.com Reply

Log in

Don't have an account? Sign up now