Samsung released a new version of Magician and a new 840 EVO firmware. Are the troubles finally over?
The tale of the Samsung 840 EVO is a long and winding one, with many hitches along the way. Launched at the Samsung 2013 Global SSD Sumit, the 840 EVO was a unique entry into the SSD market. Using 19nm planar TLC flash, the EVO would have had only mediocre write performance if not for the addition of a TurboWrite cache, which added 3-12GB (depending on drive capacity) of SLC write-back cache. This gave the EVO great all around performance in most consumer usage scenarios. It tested very well, was priced aggressively, and remained our top recommended consumer SSD for quite some time. Other editors here at PCPer purchased them for their own systems. I even put one in the very laptop on which I'm writing this article.
An 840 EVO read speed test, showing areas where old data had slowed.
About a year after release, some 840 EVO users started noticing something weird with their systems. The short version is that data that sat unmodified for a period of months was no longer able to be read at full speed. Within a month of our reporting on this issue, Samsung issued a Performance Restoration Tool, which was a combination of a firmware and a software tool that initiated a 'refresh', where all stale data was rewritten, restoring read performance back to optimal speeds. When the tool came out, many were skeptical that the drives would not just slow down again in the future. We kept an eye on things, and after a few more months of waiting, we noted that our test samples were in fact slowing down again. We did note it was taking longer for the slow down to manifest this time around, and the EVOs didn't seem to be slowing down to the same degree, but the fact remained that the first attempt at a fix was not a complete solution. Samsung kept up their end of the bargain, promising another fix, but their initial statement was a bit disappointing, as it suggested they would only be able to correct this issue with a new version of their Samsung Magician software that periodically refreshed the old data. This came across as a band-aid solution, but it was better than nothing.
Now we have the fix and I can report on what it is actually doing and accomplishing. I've been working with the new firmware and a beta version of Magician 4.6 (to be released today as I understand). Before getting into the actual results, I'll post the Q+A I had with Samsung as we were testing. This should explain at least what we expect to see:
Q: The new firmware appears to restore read performance without the need for Magician. How was this accomplished?
A: Samsung revised the firmware algorithm to maintain consistency in performance for old data under exceptional circumstances. Therefore, read performance was restored without the need for Magician. This algorithm is based on a periodic refresh feature that can maintain the read performance of this older data. The algorithm does not affect normal user scenarios (i.e. occasional PC performance degradation due to background work of SSD) or the lifespan of an SSD and can actively maintain its performance without the help of Magician. However, this algorithm does not operate when the power is off.
Q: Are there any functions of the new Magician that are required to keep read performance high?
A: The read performance has been improved by the revised firmware algorithm. If performance recovery is slow in instances where the SSD did not have enough run-time for the firmware algorithm to reach normal performance levels, or similarly, had been powered off for an extended amount of time, the performance can be recovered by using the Advanced Performance Optimization feature in Magician 4.6. This is a supplementary feature to maintain normal performance for a few exceptional circumstances.
Q: What is the upgrade process for those who did not previously upgrade using the performance restoration tool (meaning they are still on the original firmware)? Is it possible to skip directly to this new firmware and not use the performance restoration tool?
A: Users can upgrade to the new firmware through Magician 4.6, without using the performance restoration tool.
Q: Will there be a firmware update for the other Samsung TLC-based SSD models that have also demonstrated this read performance issue? If so, which models and how soon will that firmware be made available?
A: This issue had been reported for the 840 EVO SSD only.
**Edit** The new firmware will be available 'later this month'.
…so we have a firmware that can do its own periodic refreshing of data, along with an 'Advanced Performance Optimization' that can be triggered from within Samsung SSD Magician. Those that had not updated their 840 EVO before this update can skip directly to the new firmware without the need to run the old 'Performance Restoration Tool'. We were a bit disappointed to see Samsung still ignoring their other TLC SSDs, on which many have reported seeing the same type of slow down (us included), but we've pushed that one about as hard as we could. For now, lets focus on the 840 EVO and see if this fix is really what it claims to be.