Like many companies with enterprise-oriented offerings, SanDisk has its own suite of features designed to improve write endurance, data integrity, and the drive's overall reliability. The company groups these technologies under the Guardian umbrella. Individually, they're called FlashGuard, DataGuard, and EverGuard.
FlashGuard
Typical MLC-based SSDs, especially those with sub-20 nm flash like SanDisk's Optimus Eco, you can typically expect endurance rated at less than one complete drive write per day. That's more than enough for most read-intensive environments, but not nearly what you'd want in a taxing write-heavy application. Unfortunately, as manufacturing technology advances, the only way to maintain high-end endurance at the NAND level is paying more for specially-binned eMLC or SLC memory.
SMART, prior to getting purchased by SanDisk, spent years characterizing the behavior of MLC flash and thinks it has the answer. During NAND validation (in this case, 19 nm MLC), data is collected and parameters are calculated to facilitate maximum write endurance per cell. Signal processing is then used to modify those parameters based on the actual performance of each drive once it's in the field.
SanDisk also knows that write endurance varies. Instead of treating every cell as identical, it modifies its wear-leveling algorithm so that stronger cells are exposed to more writes than weaker ones.
The combination of these discoveries and features is why SanDisk is confident its Optimus Eco can withstand three to seven DWPD over the course of its five-year warranty without experiencing write exhaustion.
DataGuard
Also like most other enterprise-class products, the Optimus Eco has a fairly substantial list of reliability-oriented capabilities. It claims to feature improved error detection and correction algorithms to ensure data integrity. SanDisk also offers its F.R.A.M.E. (Flexible Redundant Array of Memory Elements) technology, which allows for cross-die redundancy to safeguard against page or block failure.
EverGuard

As we saw from our photo tour of the Optimus Eco's PCB, the drive employs a number of poly tantalum capacitors to protect against untimely data loss. SanDisk calls this EverGuard. Again, if there is information in flight when the power goes out, the caps provide just enough juice to commit data to memory so that nothing is lost.
- Meet SanDisk's Optimus Eco SSD, With Up To 2 TB
- Under The Hood Of SanDisk's Optimus Eco
- SanDisk's Guardian Technology, Broken Down
- Testing SanDisk's Optimus Eco
- Results: 4 KB Random Performance And Latency
- Results: Performance Consistency
- Results: Enterprise Workload Performance
- Results: Sequential Performance
- Results: Enterprise Video Streaming Performance
- SanDisk Takes On Intel's Enterprise SSD Crown
Every single one-second average falls between 28,500 and 38,000 IOPS (0.84 and 1.12 ms)
The Samsung Pro is not an enterprise drive. They were comparing Intel's enterprise drive vs Sandisk's.
Many consumer SATA drives are a lot less, but enterprise drives aren't always quite that low. The S3700, at 800GB, is 6W typical and 8W burst. The Eco isn't quite as 'eco' at 400GB, but for 2TB, is actually pretty good. Many of the PCIe add-in SSDs that provide better performance at the same capacity are at least 10-15W and sometimes 25W. There aren't a lot of 6Gbps SAS SSD comparisons, now that 12Gbps drives are out, but even the Toshiba MK line is rated at 6.5W. We plan on doing more power consumption testing in the future.
As was said earlier, the Samsung 840 products are not enterprise class. They do not provide the endurance or power loss protection. They could possibly be used in workstations, but not beyond that. Samsung does offer the 843T, but that product is more in line with the Intel S3500 and does not have the random write performance to come close to the Eco. The 843T is also much more expensive than the 840 series.
When comparing to HDD, there isn't a single SSD that will come close on price, enterprise or not. On the flip side, there isn't a single HDD that can come close on performance either. In order to get that much flash storage, you were previously limited to multiple SSDs or PCIe add-in cards, the Eco allows you to have that capacity in a smaller form-factor while drawing less power. Considering the $/GB, which is in line for it's class, it makes sense since there are plenty of enterprise customers buying 800GB drives, at least enough that companies keep producing them.
Every single one-second average falls between 28,500 and 38,000 IOPS (0.84 and 1.12 ms)
No, we didn't, but can you be a little more clear with your question? I am not an expert in the area, but the law, as it applies to performance testing, is valid if the number of jobs in the system is equal to those being completed. Meaning that no new jobs are created in the system and no jobs are lost forever. So, if jobs were being lost, you might see consistent performance centered around the bottleneck, which is not the device under test. Since the system is artificially creating and tracking IOs, I don't believe any are being lost or accidentally created. Also, with our Enterprise Video testing, which I wrote to test a specific use-case, the data is generated and validated as it is written, so there is no chance of data loss. If that doesn't answer your question, please let me know, I am always interested in new subjects....