Let me back up a little – they’re not really slow. When Intel compared its standard NAND flash based PCIe SSD to a similar SSD based on 3D XPoint memory, the XPoint model ran 7-8 times faster, which is very impressive. Intel demonstrated that at the Intel Developer Forum (IDF) last August and several times since then.
But Intel and Micron have been boasting since its introduction that 3D XPoint Memory is 1,000 times as fast as NAND flash. How do you get from a 1,000 times speed advantage down to a speed improvement of only 7-8 times?
That’s what the graphic in this post will explain. The small rendition above is just Continue reading
The SSD Guy was recently asked whether HDDs would continue, at least through 2019, to remain preferable to SSDs as cost-effective high-capacity storage. The answer was “Yes”.
Longtime readers will note that I steadfastly maintain that HDD and SSD gigabyte prices are unlikely to cross for a very long time. Historically, a gigabyte of NAND flash has cost between ten to twenty times as much as a gigabyte of HDD. Let’s look at where Objective Analysis expects things to go by 2019.
Our current projections call for NAND price per gigabyte to reach 4.4 cents in 2019. I would expect for HDD to still be 1/10th to 1/20th of that price. Most likely 1/10th, since we expect for NAND flash to be in a significant oversupply at that time and will be selling at cost.
If HDD prices continue to hover around $50, then a 2019 HDD price of 0.44 to 0.22 cents per gigabyte (1/10th to 1/20th of the price of NAND flash) would imply an average HDD capacity of 11-23TB.
A couple of weeks ago, on December 2, 2015, Western Digital’s HGST introduced its Continue reading
This replacement for the company’s Z-Drive 4000 series is a complete redesign with an obsession for performance. OCZ tells me that they moved from a 2-hop design to a 1-hop by using the PMC Princeton PCIe SSD controller, and have passed the University of New Hampshire Interoperability Labs’ compliance tests to NVMe 1.1B compliance.
But how does it perform? Well the 1-hop design helps reduce latency (which is just starting to overshadow IOPS in users’ minds) and the latency of this SSD is significantly lower than competing NVMe SSDs: between 25-30μs, figures that OCZ tells me are very consistent, a big plus for enterprise applications. As for IOPS, the device can perform under a 70/30 Read/Write load at 330K.
The 6000 series is provided in both standard MLC and eMLC for those who want the security of eMLC and are willing to sacrifice a little performance to sleep better at night.
This product is a good fit for the market needs, and shows how devoted OCZ and its parent Toshiba are to providing high performance in the SSD marketplace.
What is NVRAM? Quite simply, it’s DRAM or SRAM that has a back-up flash memory a small controller, and a battery or super-capacitor. During operation the DRAM or SRAM is used in a system the same way that any DRAM or SRAM would be used. When power is interrupted the controller moves all of the data from the DRAM or SRAM to the flash using the backup power from the battery or super-capacitor. When power is restored, the controller moves the contents of the flash back into the SRAM or DRAM and the processor can resume operation where it left off.
In some ways it’s storage and in some ways it’s memory, so Continue reading
I have just added a new white paper onto the Objective Analysis website: Matching Flash to the Processor – Why Multithreading Needs Parallelized Flash.
This document examines the evolution of today’s CPUs, whose clock frequencies have stopped increasing, but now exploit parallelism to scale performance. Multiple DRAM channels have also been added to performance computing to add parallelism to the memory channel.
Storage hasn’t kept pace with this move to parallelism and that is limiting today’s systems.
New NAND flash DIMMs recently introduced by Diablo, SanDisk, and IBM, provide a reasonable approach to adding parallel flash to a system on the its fastest bus – the memory channel. This white paper shows that storage can be scaled to match the processor’s growing performance by adding flash DIMMs to each of the many DRAM buses in a performance server.
The white paper is downloadable for free from the Objective Analysis home page. Have a look.
I can already hear readers saying: “Wait! You can’t do that!” Well, you’re right, but the new module comes awfully close to that by putting the NAND behind an ASIC that interfaces between the DDR3 bus and the NAND.
Why do this? Quite simply because you can get more “Bang for the Buck” by adding NAND to the system once you’ve reached a certain DRAM size. The Diablo “Memory Channel Storage” (MCS) approach supports the addition of terabytes of NAND at the loss of Continue reading
In case you didn’t have enough abbreviations in your life, The SSD Guy brings you the headline above, with the promise that the news below is really interesting: HGST (formerly Hitachi Global Storage Technology, but now a division of WDC – Western Digital Corp.) has brought out a new line of 12Gb/s SAS SSDs based on MLC flash. These are a part of the UltraStar line.
Whereas HGST’s first-generation UltraStar SAS SSDs used SLC flash, the new SSDs are based on 25nm MLC flash but offer the same warranties as HGST’s prior generation. Even so, performance for the new SSDs is significantly faster than that of their SLC-based predecessors, with no reduction in wear or lifetime specifications.
These SSDs are the first to support Continue reading
Lately a number of PCIe offerings have hit the SSD market. The SSD Guy breaks them into two camps: One-Hop SSDs, in which the commands are translated directly from PCIe to the NAND flash without going through an intermediary protocol, and Two-Hop SSDs, which use off-the-shelf HBAs and SATA SSD controllers to move commands first from PCIe to SATA then from SATA to NAND. There are aslo versions that go through SAS: PCIe to SAS, then SAS to NAND.
The SSD Guy figured that Easter would be a good time to talk about these since everyone already has the Easter Bunny hopping through their minds!
It’s not hard to understand why Continue reading
Today Intel announced a new SATA III SSD, the DC S3700 Series. The new product is fast, supporting 75,000 random 4K read IOPS and 36,000 random 4K write IOPS. Average read latency is 45microseconds (µs) with writes averaging 65µs. Sustained sequential reads are 500 megabytes/sec with sustained sequential writes at 460. The read performance of this SSD, although a SATA device, is twice that of Intel’s 710 PCIe SSD announced in April, and writes are a full 15 times faster. Intel calls this performance: “Scary fast!”
Intel says this device is its best Continue reading