Jim Pappas of Intel, a fellow member of SNIA (the Storage Networking Industry Association) shared a really intuitive way to understand storage delays at the last Storage Developer Conference (SDC). It’s very simple. First consider these two facts:
- The difference between the speed of system memory and that of a hard disk drive (HDD) is roughly 6 orders of magnitude, or 1 million times
- SSDs split the gap. An SSD is about 1,000 times faster than an HDD, and is about 1,000 times slower than system memory. Memory access times are measured in nanoseconds (ns), SSDs in microseconds (µs) and HDDs in milliseconds (ms)
The problem with understanding this (ns, µs, ms) is that Continue reading “Understanding Storage Delays”
One of the best arguments to use an SSD is also one of the most difficult ways to sell anything. This is the Total Cost of Ownership, commonly abbreviated to “TCO.”
TCO has been used as an argument for buying anything from compact fluorescent bulbs to Jaguar automobiles.
The argument usually revolves around an item whose initial price is higher, but which has lower ongoing (or operating) costs, and when these costs are combined, the higher-priced item proves to cost less to own over the long run. In the case of a compact fluorescent (CF) bulb, the bulb may cost $7, versus $1 for an incandescent bulb, but it consumes 18 Watts compared to the 75 Watts consumed by the incandescent bulb it replaces. In addition the CF bulb lasts ten times as long (10,000 hours vs. 1,000 hours.) This works out to a savings of 470 kWh – or about $50 – plus $3 in bulb costs. Continue reading “SSDs and TCO”
SNIA (The Storage Networking Industry Association) has conferred a great honor upon the SSD Guy by bringing all of the blog posts in the series How Controllers Maximize SSD Life into a single printed volume of the same name.
Readers can either ask for a print copy from SNIA, or can download a pdf rendition by visiting the SNIA SSSI (Solid State Storage Initiative) education web page.
Few Sysadmins really understand what’s happening in the storage interface of their systems, yet there’s a lot of talk about SSDs with wide-ranging IOPS figures along with case studies of how these have helped solve system slowdowns. The big question is: “How do you determine what your storage bottleneck is, and even whether or not one exists at all?”
Tom Coughlin and I discovered a very low level of understanding of this issue when we performed the IOPS survey late last year that we documented in our report: How Many IOPS do You Really Need? A disconcerting number of respondents gave replies that Continue reading “How to Locate a Storage Bottleneck”
Last week the Storage Networking Industry Association (SNIA) hosted its 2012 Storage Developer Conference (SDC). There was a strong focus on SSDs at this forum, with 15 papers, one keynote, and a panel devoted to the subject.
Consider that the 2008 SDC was the first such conference in which SSDs were discussed. This year I commented to another participant: “Some day we will look back on this transition and be amazed at how suddenly SSDs became fundamental to the way storage is configured!”
Many of those papers and keynotes made it clear that the PCI Express (PCIe) interface has Continue reading “Storage Developer Conference Focuses on SSDs”
SSDs vary widely in performance. This is something that becomes amazingly clear when a number of these devices are put through a battery of tests.
Calypso Systems ran the SNIA SSD Performance Test Specification (PTS), outlined in an earlier post in this blog, on seventeen SSDs and a single HDD. The results appear, in miniature, in the graphic for this post. Continue reading “Not all SSDs are Created Equal”
The Storage Networking Industry Association – SNIA – determined a few years back that it should address SSDs since they were about to become an important part of most storage systems. To this end SNIA created the Solid State Storage Initiative, or SSSI.
They didn’t name it after SSDs since there will clearly come a time when flash stops pretending it’s an HDD and abandons standard HDD mechanical and interface specifications. Continue reading “What’s the SNIA SSD Performance Test Specification (PTS)?”