New Samsung SSD 840 EVO Read Performance Fix Coming Later This Month

An anonymous reader writes: The Samsung SSD 840 EVO read performance bug has been on the table for over six months now. Initially Samsung acknowledged the issue fairly quickly and provided a fix only a month after the news hit the mainstream tech media, but reports of read performance degradation surfaced again a few weeks after the fix had been released, making it clear that the first fix didn't solve the issue for all users. Two months ago Samsung announced that a new fix is in the works and last week Samsung sent out the new firmware along with Magician 4.6 for testing, which will be available to the public later this month.

Comments

Too late; already sold my EVO's on eBay

[SplatMan_DK]

Six months is not an acceptable time to wait for a performance fix for an SSD drive. The very essence of an SSD is "speed".

I offloaded the EVO's on eBay (being honest about the reason) and got myself a couple of Plextor Pro drives. Running in RAID0 they are a bit slower at random reads than the EVOs, but faster at sustained transfer rates.

An SSD with slow/degraded performance is like a burger without the beef... something is missing...!

Re:Too late; already sold my EVO's on eBay

[davester666]

Good. Fast. Cheap.

You bought Samsung, so you picked cheap.

Re:Too late; already sold my EVO's on eBay

[SplatMan_DK]

Not quite. The specs on the EVO 840's are actually very good ... if only they lived up to them!

If this new fix actually works, the EVO's will be a very good buy. Pretty reliable too according to tests. I just couldn't wait (and had no idea if/when a fix was ever going to surface).

Re:Too late; already sold my EVO's on eBay

[SplatMan_DK]

Hey, why the attitude man? Did it somehow offend you that I decided to replace the drives? Are you so emotionally attached to your own identity as an EVO customer that you must attack people who choose differently?

I used the EVO 840 from virtually the same week they became available. Performance was great, but it slowly degraded with time passed. The decrease was very visible for large blocks of data which were read often but not refreshed or updated. Not just on synthetic benchmarks. My usage pattern fits that bill because I use several virtual machines that are 40 - 120 GB large, and only a small portion of their virtual disk files are changed (SQL database files). Moving the virtual machine to an external drive and back on to the SSD's solved the problem, but shuffling around 120 GB virtual servers in order to "keep the memory cells happy" is a chore I'd rather be without.

Perhaps the issue was more visible to me because I run 2 drives in RAiD0 which means I get hit by the degradation twice - once for each drive. Never the less, the issue was very real to me. YMMV off course, but please accept that your own perception of this issue is not the universal truth.

In regards to your snarky comment about me being a "savvy consumer": Yes, I believe I am a reasonably savvy consumer when it comes to SSD drives. I am a Business Intelligence specialist and I am quite confident in my ability to understand and evaluate disk read performance. It is part of my job. When analyzing large amounts of data or operating virtual servers (booting or resuming), sustained data transfer is very important. The slightly lower random read performance of my Plextor Pro drives is a very good trade-off for the added sustained transfer rate. In addition the Plextor pro drives use a server-grade controller chip with a GC routine that works very well without TRIM. Since I operate in RAID mode that is also a concern when I buy drives. My Laptop does not support TRIM in RAID mode (desktop/gaming rig does though).

Not everybody on the planet uses their computer in exactly the same way as you do.

Re:Too late; already sold my EVO's on eBay

[swb]

It looks like a serious degredation of peformance from the perspective of the difference between what the drives should be capable of versus what the bug limits them to, but the GP poster sort has a point in that the drive's performance doesn't seem to be dropping even to the level of a USB3 flash disk let alone a mechanical SATA disk.

Obviously nobody but the actual user of a specific setup would know whether or not it was burdensome, but I would be kind of surprised if it was generally noticable. I see a lot of commercial SANs in use by medium sized enterprises as backing stores for VM host clusters consisting of TBs of data used by SQL, SMB, Exchange that don't exceed 1000 IOPS and 75 MB/sec.

If this represents a real business workload, I would be kind of curious to know what kind of a workload you'd have to present to a stripe set of SSDs to see the effects of this performance bug. The linked article shows some kind of performance graph hitting a low of 100 MB/sec sustained read. A raid 0 stripe would be close to 200 MB/sec sustained read at worst. Maybe you'd notice it, but it seems like a pretty unusual workload that would expose this.

Raises a point about tech reviews

[RogueyWon]

I shifted to an SSD for my OS and core applications (plus a few disk-speed sensitive games - a fast-growing category) last year. I'd been planning to buy the 500gb 840 EVO, but, by some small miracle, Amazon had a special on the 840 Pro on the weekend I made my purchase, putting its price very close to the EVO, so I bought that instead. The 840 Pro is apparently not affected by this. Phew, bullet dodged.

But it's interesting that the issue is picked up in so few reviews. Indeed, there's a veiled apology for this in an ExtremeTech article about the bug from October. Reviews are generally carried out on the basis of a short but intensive testing period and hence don't pick up serious issues that take a bit of time to show up.

That's obviously been particularly important in this case, due to the specific nature of this bug. But when it comes to expensive bits of hardware like SSDs and high-end graphics cards, I'd be interested in reviews which came out a bit later but gave a better reflection of failure rates and longer-term issues. I've been stung before by buying a well-reviewed graphics card which turned out to have a horrible failure rate over time.

Re:Raises a point about tech reviews

[Anonymous Coward]

Unfortunately, most of the sites that do reviews survive thanks to their readers. Which means they can't afford to wait 6 months after product release to publish. By that time, most of their competition has taken their views.

Re:EVO 850

[jones_supa]

I'd expect the TLC FLASH in the 850 EVO to be much more robust against this sort of issue, being of a much bigger process size (50nm?) and suffering less electron leakage as a result.

The bug is absolutely not caused by electron leakage! Flash drives would be dying all the time if that was the case.

Re:Yay

[goarilla]

Their first fix came out as a windows program and later as a live cd. The Windows program used free ntfs space to shuffle data around.
The live cd did not need a NTFS system and it did not eat my data. (ext4 + LVM2 + md-raid)
I suspect this fix will get a corresponding live cd as well, so we'll just have to wait a little bit longer.