Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[newsposter]

It looks like SSDs 750Gb and larger are going for good prices on Amazon, et al.

Over the weekend I picked up a 1 Tb Samsung 850 EVO for $199- shipped on a one-day sale.  There are similar deals from other sellers.

For those of you with a MicroCenter in your area, they have Sansung and Crucial SSDs at good prices as well.

[trajanmcgill]

Where did you find this? I see no 1TB 850 Evos for any less than $337 anywhere.

[BernhardS]

I think he meant 750 GB

[marko]

After three years, my Samsung 840 Pro SSD has started a daily stream of reallocated sectors. Up to 148 now, but SMART states the drive is still OK and Samsung won't RMA it. Guess I'll have to wait until it fails completely.

Not impressed though. The Samsung drive was highy recommended.

[Hendrik]

The more interesting question would be how much data you have actually written to it. Time is of no consequence for these drives (well, not as much anyway), just data written.

Endurance tests on the 840 Pro have shown that it can start re-allocating sectors but still go strong for hundreds of terabytes. In this particular test it started collecting sectors rapidly after 700TB of written data, but didn't die until over two Petabytes of data had been written to it.
These numbers are usually far above their rated endurance, fwiw.

In this test, the 840 Pro also outlived many of its competitors, being one of two to reach the 2PB mark (while the others died before).

Note that this is specifically the "Pro" drive, they also tested a 840 "Basic" in the same test, and it died much earlier.

[marko]

Interesting. According to their Magician software, "total bytes written" is 9.24 TB

HD Sentinel predicts drive failure in 74 days.

[jmone]

RMA it?

[marko]

Samsung support are saying "No" because it's passing SMART, "all OK"

Guess I'll need to wait until it dies.

[jmone]

That's interesting, I've had no prob RMAing HDD using a print out from HDS before (but not a Sammy)

[marko]

Hopefully newsposter doesn't mind me hijacking this thread, maybe it should be split anyway?

Anyhoo...
Sectors continue to be reallocated daily. It's got to the point where I've started to dismiss the daily HDS alerts out of hand, without evening checking the drive. I'm up to 610 now...
It's not really computing for me. How can I be getting this...


but SMART says it's all OK...


I asked the chap at Samsung support how high this value could go before SMART reported that it was not OK, and am still waiting for (given up on getting) his answer.

Strange behaviour (from the drive). I'm not seeing any real-time issues in daily use, just this creeping reallocated sector count that has HDS freaking out at me

-marko

[mwillems]

The disk has a reserved area that it uses to compensate for bad sectors.  So when the disk hits a bad sector it just marks it as "bad" opens up a sector in the reserved area (that's the "reallocation").  So up to a certain point the disk is working as intended by reallocating bad sectors and there's no immediate data risk.  In Tech Report's study, the 840 Pro at one point had logged 5591 reallocated sectors and that represented about 61% of the reserve on a 256GB drive. It ultimately failed after logging over 7000 reallocated sectors.  But their drive showed a smooth linear increase whereas yours is showing exponential growth, which is troubling.

So assuming that exponential curve of bad sectors keeps up, it's going to blow past the available reallocation space in a few more months; I have no idea how Samsung can credibly say that this isn't pre-failure behavior.

[InflatableMouse]

You know what I would do?

Simply start writing data to the disk 24/7 until it fails and RMA it.

Samsung is not a pleasant company to deal with and their customer service kind of sucks (IMO ). You're probably not going to get decent help until it's just broke and they have no choice but to replace it.

[marko]

Thanks for the info. If these things can go into the thousands I think I'll step the HDS alerts down a little.

In their "Magician" software, I gave the drive 24Gb for 'over provisioning', but never really understood why, figuring that if the drive got tight for space, I would reclaim it. Am I correct in thinking that whatever "OP" is, it's nothing to do with spare sectors?

Do a mercy killing on it? Interesting idea... I'll give it some thought over the next week or so...

[InflatableMouse]

Overprovisioning is not used for reallocated sectors, but for performance for the drive to use as a "scratch area" when it is getting full. Reallocated sectors is a reserved, designated area on the drive that you can't touch or claim for storage.

[InflatableMouse]

I need to add something to the comment above.

I just ran into a discussion about overprovisioning with someone else, and it seems that the term is being used for different things.

Manufacturers use the term overprovisioning for the non-user space as a means to provide the controller with space for reallocated sectors. You and I can never reach this space unless a sector is being reallocated. The SSD is actually a few percent larger than what we get to see as users and that is the over provisioning.

% Over provisioning = (Physical Capacity - User Capacity) / User Capacity
link: http://www.kingston.com/en/ssd/overprovisioning

Samsung uses the term overprovisioning in their Magician software, which refers to making the user partition smaller than the total usable space. So, it takes the 256GB usable space, creates a 200GB partition and leaves 56GB unpartitioned. This has got nothing to do with hardware over provisioning for reallocated sectors.

When I replied above, I was referring to the Samsung definition of overprovisioning as you're using a Samsung drive and mentnioned using the Magician software. I didn't realize the hardware over provisioning was actually also referred to as overprovisioning.

Confusing ... sorry.

[marko]

Well now...

I hit 713 reallocated sectors on 22nd... and no more since. It's plateaued at 713 for week now.

In the sprit of the OP, I almost bought a 240Gb Sandisk SSD from eBuyer for £45, but held off... There might be life in this Samsung drive after all.

-marko