Revision History Published: 27 Dec 2013 - first published Updated : 28 Dec 2013 - add TODO list of Samsung 840 and Crucial M500 Updated : 29 Dec 2013 - add Editor's note after slashdot article Updated : 1 Jan 2014 - Add stec-inc S230 SATA Slim Editor's note 29Dec2013 Thank you for everyone's input from the Slashdot story. The additional drives for consideration is extremely useful but they will have to go through the same process of cost-benefit - followed only then by reliability - analysis that the other drives went through, with the additional handicap that the Intel S3500 has already "won" and been selected for live deployment. Which brings me to a keen point that is difficult to express when there are 275 slashdot comments to contend with. The belief that Intel paid for this report comes through loud and clear. Those who believe that are severely mistaken. Let's look at it again. Statement of fact: The S3500 SSD happens to be the sole drive which a) is cost-effective b) passed all the extreme tests c) is within budget d) was clearly marked in the online marketing as "having power loss protection" e) is not end-of-life So let us be absolutely clear: Fact: the Intel S3500 was the only drive which matched the requirements That it did so so completely comprehensively despite the extreme nature of the testing, which lasted several days whilst all other drives failed within minutes, is the real key point of this report. However that point - that success - is itself also completely irrelevant beside the fact that the testing itself provided the company that commissioned the work with an amazingly high level of confidence in "an SSD" despite their complete paranoia which had driven them to commission the testing in the first place. To make that clear: The company doesn't care about Intel: they care about a reliable drive If there were other drives that had passed or were known about or could have been found, they would have been added to the list already. Analysis of SSD Reliability during power-outages This report was originally commissioned due to the remote deployment of over 200 32gb OCZ SSDs resulting in severe data corruption in over 50% of the units. The recovery costs were far in excess of the costs saved by purchasing the cheaper OCZ units. They were replaced rapidly over a period of years by Intel SSD 320s, where, despite remote deployment of over 500 units there have only ever been three unrecoverable failures. However, the Intel 320 SSD has reached end-of-life, so a replacement was sought. Due to paranoia over the OCZs an in-depth analysis was requested. Around the time that the paranoia was hitting, a report had come out on slashdot, covering power-related corruption. It made sense therefore to attempt to replicate that report, as it was believed that the data corruption of the OCZs was related to power loss. This report therefore covers the drives selected and the testing that was carried out. We follow up with a conclusion (summary: if you care about power loss don't buy anything other than Intel SSDs - end of story) and some interesting twists. Picking drives for testing The scenario for deployment is one where huge amounts of data simply are not required. An 8gb drive would be able to store 1 month's worth of sensor data, as well as have room for a 1.5gb OS deployment. A 16gb drive stores over two months. Bizarrely, except in the Industrial arena the focus is on constant increases in data storage capacity rather than data reliability. The fact that shrinking geometries automatically results in higher susceptibility to data corruption is left for another time, however. Additionally, due to the aforementioned paranoia and assumptions that the data loss was occurring due to loss of power, the requirements to have "Power Loss Protection" were made mandatory. Power Loss Protection is usually found in Industrial and Server Grade SSDs, which are typically more expensive. So, finding low-cost low-size reliable SSD reported to have "Power Loss Protection" proved... challenging. After an exhaustive search, the following candidates were found:

Crucial M4 128gb

The unpronounceable Toshiba THNSNH060GCS 60gb

The new Intel S3500

The Innodisk 3MP Sata Slim (8gb and 16gb)

OS-based test. The first test devised was to boot up a full OS and to power-cycle it using a mains timer. This test turned out to be completely lame, except for its negative results proving that simply switching power on and off was not the root cause of problems.

The first test devised was to boot up a full OS and to power-cycle it using a mains timer. This test turned out to be completely lame, except for its negative results proving that simply switching power on and off was the root cause of problems. OS-based huge parallel writes. The second test was to write huge numbers of files and subdirectories in parallel. Thousands of directories and millions of small files as well as one large one were copied, sync'd then deleted using 64 parallel processes. Power was not pulled during this test.

The second test was to write huge numbers of files and subdirectories in parallel. Thousands of directories and millions of small files as well as one large one were copied, sync'd then deleted using 64 parallel processes. Power was pulled during this test. Direct disk writing. This test was closer to the original FAST report, except simplified in some ways and extended in others.

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