Sequential Read/Write Speed

To measure sequential performance I ran a 1 minute long 128KB sequential test over the entire span of the drive at a queue depth of 1. The results reported are in average MB/s over the entire test length. These results are going to be the best indicator of large file copy performance.

Desktop Iometer - 128KB Sequential Read (4K Aligned)

Desktop Iometer - 128KB Sequential Write (4K Aligned)

Again we see that low queue depth transfers don't stress the Z-Drive enough to flex its muscles.

Sequential Performance vs. Transfer Size (ATTO)

I stopped putting these charts in our reviews (although I do include the data in Bench) because they are generally difficult to read. Here we're only going to look at three drives though: a Vertex 3, RevoDrive 3 X2 and the Z-Drive R4 CM88:

Now we're starting to see something. If you can't scale with queue depth, scaling up the transfer size seems to do the trick. After about 64KB the Z-Drive R4 starts to pull away fro the RevoDrive 3 X2, peaking at just over 2.5GB/s!

Read performance is even more impressive: the Z-Drive R4 manages just under 3GB/s for 2MB transfer sizes.

Random Read/Write Speed AS-SSD Incompressible Sequential Performance
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  • caliche - Wednesday, September 28, 2011 - link

    I am sure he is referring to the previous versions of the z-drive, which is all you can use as an indicator.

    I am an enterprise customer. Dell R710s and two Z-Drive R2 M84 512GB models, one in each. I have had to RMA one of them once, and the other is on it's second RMA. They are super fast when they work, but three failures across two devices in less than a year is not production ready. We are using them in benchmarking servers running Red Hat Enterprise 5 for database stores, mostly read only to break other pieces of software talking to it. Very low writes.

    But here is the thing. When they power on, one or more of the four RAID pieces is "gone". This is just the on board software on the SSD board itself, no OS, no I/O on it at all besides the power up RAID confidence check. Power on the server, works one day, next day the controller on the card says a piece is missing. That's not acceptable when you are trying to get things done.

    In a perfect world, you have redundant and distributed everything with spare capacity and this is not a factor. But then you start looking at dealing with these failures and you start to ask yourself is your time better spent on screwing around with an RMA process and rebuilds or optimizing your environment?
  • ypsylon - Thursday, September 29, 2011 - link

    Nobody in the right frame of mind using SSD in enterprise segment (not even interested in them as consumer drives, but that is not the issue here). SSDs are just as unreliable as normal HDDs with ridiculous price point. You can lose all of data much quicker than from normal HDD. RAID arrays built from standard HDDs are just as fast as 1 or 2 "uber" SSDs and cost fraction of a SSD setup (often even including cost of the RAID controller itself). Also nobody running large arrays in RAID0 (except maybe video processing). RAID0 is pretty much non-existent in serious storage applications. As a backup I much more prefer another HDD array than unreliable, impossible to test, super-duper expensive SSD.

    You can't tests NAND reliability. That is the biggest problem of SSDs in business class environment. Because of that SSD will whiter and die in the next 5-10 years. SSDs are not good enough for industry, if you can't hold on to big storage market then no matter how good something is, it will die. Huge, corporate customers are key to stay alive is storage market.
  • Zan Lynx - Thursday, September 29, 2011 - link

    You are so, so wrong.

    Enterprises are loving SSDs and are buying piles of them.

    SSDs are the best thing since sliced bread if you run a database server.

    For one thing, the minimum latency of a PCIe SSD 4K read is almost 1,000 times less than a 4K read off a 15K SAS drive. The drive arrays don't even start to close the performance gap until well over 100 drives, and even then the drive array cannot match the minimum latency. It can only match the performance in parallel operations.

    If you have a lot of operations that work at queue depth of 1, the SSD will win every time, no matter how large the disk array.
  • leonzio666 - Wednesday, November 2, 2011 - link

    Bear in mind though, that enterprises (real heavy weights) probably preffer something like fusion-io io-drives which btw are the only ssd`s running in IBM driven blade servers. With speeds up to 3 Gb/s and over 320 k IOPS it`s not surprising they cost ca 20k $$ per unit :D So it`s not true that SSD`s in general are not good for the enterprise segment. Also, and this is hot - these ssd use SLC NAND...
  • MCS7 - Thursday, September 29, 2011 - link

    I remember Anand doing a VOODOO 2 card review (VIDEO) way way way back at the turn of the millenium! Oh boy..we are getting OLD....lol take care all
  • Googer - Thursday, September 29, 2011 - link

    Statistics for CPU usage would have been handy as some storage devices have greater demands for the CPU than others. Even between various HDD makes, CPU use varies.
  • alpha754293 - Thursday, September 29, 2011 - link

    Were you able to reproduce the SF-2xxxx BSOD issue with this? or is it limited to just the SF-2281?

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