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Investigation: Is Your SSD More Reliable Than A Hard Drive?

tomshardware.com

21–30 of 53 posts

Re: Investigation: Is Your SSD More Reliable Than A Hard Drive?

#21
post #6

Consider this: the hard drive is the least reliable component of almost any modern PC/laptop. Add to this that it likely contains the most valuable non-commodity asset: your data. Anyone not backing up their system is really asking for trouble... which will happen. Given the ease of use of modern backup systems, and their cost (free only costing a modest amount of your time), everyone should be doing it. OSX and Win7…

> and their cost (free only costing a modest amount of your time)

Unfortunately it is not. You pay for it either in bandwidth and service price (or in reliability of free service) or by buying a new harddrive.

Cost of a 500GB drive is rather far from "free".

Re: Investigation: Is Your SSD More Reliable Than A Hard Drive?

#22
I remember reading early on when SSD first came out where people claimed that when SSD fails, it fails into a read-only state so at least you do not lose your data.

But apparently this is not true and it's not how SSD fail, at all.

What's crazy is I have not had a hard drive fail since we passed the triple digit mark for GB capacity. Last one was a 20GB drive (ah the old days).

Re: Investigation: Is Your SSD More Reliable Than A Hard Drive?

#23
post #6

Consider this: the hard drive is the least reliable component of almost any modern PC/laptop. Add to this that it likely contains the most valuable non-commodity asset: your data. Anyone not backing up their system is really asking for trouble... which will happen. Given the ease of use of modern backup systems, and their cost (free only costing a modest amount of your time), everyone should be doing it. OSX and Win7…

> Consider this: the hard drive is the least reliable component of almost any modern PC/laptop.

Is it really? Completely anecdotally I've never lost a HDD, but keep going through power supplies… it'd be nice to see some data on component failure rates. I assume some exists, but I haven't really felt strongly enough about it to go look.

Re: Investigation: Is Your SSD More Reliable Than A Hard Drive?

#24
post #6

Consider this: the hard drive is the least reliable component of almost any modern PC/laptop. Add to this that it likely contains the most valuable non-commodity asset: your data. Anyone not backing up their system is really asking for trouble... which will happen. Given the ease of use of modern backup systems, and their cost (free only costing a modest amount of your time), everyone should be doing it. OSX and Win7…

I disagree. In my collection of always-on 30 machines in my basement, over the last three years I have had probably 10 power supplies die, and only two hard drives. The hard drives that died--two 500 gig drives--died in the same month after just two years. I don't keep spare hard drives, but i do keep spare power supplies.

Re: Investigation: Is Your SSD More Reliable Than A Hard Drive?

#25
post #5

All these statistics come from server use, where drives are constantly spinning and kept at a relatively constant temperature. I'm curious if there's a bigger difference in laptop computers, where the drives see a lot more physical abuse, power cycles, temperature variations, etc.

I haven't quite been able to grasp why Toms Hardware, which I view largely as a consumer/enthusiast review site would choose to analyze the failure rates of SSD's in a datacenter environment. How about going to IT departments that have "floater" laptops and seeing how long the drives hold up in those? I think the primary consumer reasons for purchasing SSD's are increased battery life and physical fault tolerance in laptops not the expectation that they'll outlast a standard HDD in a server setting.

Re: Investigation: Is Your SSD More Reliable Than A Hard Drive?

#26
post #19
post #11

Earlier quoted context omitted.

I get annoyed when people make generic claims that SSDs from vendor X are not as reliable as vendor Y. The truth is that each vendor manufactures multiple lines of SSDs, each running different major firmware versions, with different hardware revisions. So reliability variance between models from a single vendor is often much more significant that variance between different vendors. In your experience with OCZ, which…

The article makes those claims, based mostly on anecdotal evidence rather than a peer-reviewed scientifically rigorous study. It concludes with: "Giving credit where it is due, many of the IT managers we interviewed reiterated that Intel's SLC-based SSDs are the shining standard by which others are measured." While an itemized breakdown by datacenter isn't available one datacenter (InterServer.net, with fewer than 10…

They generally disappeared completely, no longer being readable. Spinners die much more gracefully with an easier disk recovery.

That's a weird thing to say. In a datacenter you want your disks to be fail-fast. I.e. you want them to drop out of the array early and cleanly.

Nobody "recovers" harddrives in a datacenter, you just swap them.

The worst failure-mode (that is still way too commonly seen) is that of the "lame drive" that grows bad sectors, predictive failures and all that jazz over time, causing bus-resets, confused controllers and bringing the whole array to a crawl until a human steps in.

That said, my experience with SSDs in that regard isn't too good either. I've seen them fail cleanly but I've also seen a single failing Vertex lock up a LSI-controller hard...

Re: Investigation: Is Your SSD More Reliable Than A Hard Drive?

#27
post #11
post #8

The short summary is that nobody had used SSDs in any large scale for more than 2 years and the rates of failure for SSDs in that period of time is similar to regular hard drives. Also apparently OCZ SSDs aren't as good as Intel SSDs (based on customer return rates).

I get annoyed when people make generic claims that SSDs from vendor X are not as reliable as vendor Y. The truth is that each vendor manufactures multiple lines of SSDs, each running different major firmware versions, with different hardware revisions. So reliability variance between models from a single vendor is often much more significant that variance between different vendors. In your experience with OCZ, which…

I agree - you can't just look at brand, as there are often a lot of issues that are specific to individual models. Having said that, my experience selling OCZ drives (100s of drives) is that they all have a high failure rate :( The only drives I haven't had experience with are the Enterprise level drives, so I can't comment on them.

I think the reason for this is that OCZ largely uses Indilinx and Sandforce controllers, and while very quick, they have had more than their fair share of issues.

Re: Investigation: Is Your SSD More Reliable Than A Hard Drive?

#28
post #12

Why is the IT industry so cautious about SSD reliability? We have spent decades developing HDD fault-tolerance mechanisms or processes such as RAID and backups. We should trust them .

Because even if you have rock solid RAID and backup solutions (and unfortunately, many, many companies don't), there is a cost involved in replacing drives. Especially when you are talking about an end user. Yes, most servers have RAID and you can do a swap out with no down time, and at minimal cost. But if you have an SSD failing in a users laptop / desktop, the down time and frustration involved can be major.

Re: Investigation: Is Your SSD More Reliable Than A Hard Drive?

#29
post #12

Why is the IT industry so cautious about SSD reliability? We have spent decades developing HDD fault-tolerance mechanisms or processes such as RAID and backups. We should trust them .

We're currently trusting a drive that might fail in 5 or so years in one specific place. The rest is recoverable, the place of failure might be overwritten anyways, the data might not be needed, smart will warn you that the problem is close in many cases... With SSD you have a chance of going completely blank. If it happens to be a firmware issue on a RAID mirror, there's also a chance of common fault in both drives.…

> smart will warn you that the problem is close in many cases...

According to Google, about two thirds of the time, SMART will warn you.

> there's also a chance of common fault in both drives.

Never, ever trust a RAID array made from identical disks. Whenever possible use different manufacturers, different models and different batches. Whatever caused failure of one drive will eventually cause the failure of its twins. If all twins are in the same array, you won't be happy.

Re: Investigation: Is Your SSD More Reliable Than A Hard Drive?

#30
post #16
post #14

I wish people would compare these with IO operations instead of wall time. SSD is a huge win there, and that matters the most for a lot of people.

This is the main conclusion at the end of the article: that SSDs should be picked for their performance rather than for their reliability, as SSD reliability hasn't been proven to be better whereas performance has. Reliability comes in here because you can replace 4+ HDDs with a single SSD and thus reduce energy/heating costs and also increase reliability as you only have 1 drive that can fail vs 4+.

You should also consider the reliability of a drive decreases at the same rate the data it holds gets more important. The more important the data, the less you should trust your disks (and do better backups, better mirroring, better checksumming...
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