Someone asked how long I expected my SSDs to last. The context was swapping to SSD, but obviously it actually depends on the usage pattern as a whole, not just one aspect of it. Here’s the SMART attribute data for an Intel SSD that’s been in constant light usage, including swapping, for the last 18 months:
smartctl 5.40 2010-07-12 r3124 [i686-pc-linux-gnu] (local build) Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net === START OF READ SMART DATA SECTION === SMART Attributes Data Structure revision number: 5 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 3 Spin_Up_Time 0x0020 100 100 000 Old_age Offline - 0 4 Start_Stop_Count 0x0030 100 100 000 Old_age Offline - 0 5 Reallocated_Sector_Ct 0x0032 100 100 000 Old_age Always - 0 9 Power_On_Hours 0x0032 100 100 000 Old_age Always - 12131 12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 19 192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 5 225 Load_Cycle_Count 0x0030 200 200 000 Old_age Offline - 9248 226 Load-in_Time 0x0032 100 100 000 Old_age Always - 16301 227 Torq-amp_Count 0x0032 100 100 000 Old_age Always - 1 228 Power-off_Retract_Count 0x0032 100 100 000 Old_age Always - 1018723636 232 Available_Reservd_Space 0x0033 100 100 010 Pre-fail Always - 0 233 Media_Wearout_Indicator 0x0032 099 099 000 Old_age Always - 0 184 End-to-End_Error 0x0033 100 100 099 Pre-fail Always - 0
A couple of caveats about interpretation. Firstly, TYPE is the type of the attribute, not a commentary on its current value - i.e. the ones that say Old_age will still say that on a brand new device and Pre-fail doesn’t mean a failure is imminent. Secondly high VALUE fields are better: they mostly start at a high value (here, mostly 100) and decline as things get worse.
Anyway Media_Wearout_Indicator is the one of interest here. Intel describe this as follows:
The E9 SMART attribute reports a normalized value of 100 (when the SSD is brand new out of the factory) and declines to a minimum value of 1.
The normalized value decreases as the NAND erase cycles increase from 0 to the maximum-rated cycles. Once the normalized value reaches 1, the number will not decrease, although it is likely that additional wear can be put on the device.
So the current value means the device has performed at least 1% and less than 2% of the maximum rated erase cycles; if current usage patterns persist it’d take between 75 and 150 years to reach the maximum.
Obviously this isn’t the whole story. The device only has a three year warranty, and plenty of other things could go wrong either with the disk or the computer containing it; and Intel could have got their sums wrong. Nevertheless I’m pretty comfortable that flash wear is not going to be a problem in the near future.
- Intel SSD 330 series product specification - see s5.0 for SMART attributes
- Monitoring Media Wearout Levels of Intel Solid-State Drives
- SandForce SMART attributes - SSD_Life_Left seems to be the nearest equivalent of Media_Wearout_Indicator.
- Wikipedia page on SMART
I caught a cold about two weeks ago. I’m still coughing slightly.
I put a deep cut into my thumb while chopping vegetables this week. (There will not be photos.)
Our landline isn’t working at the moment. Now fixed.
I’m still pleased with my phone:
- I spent too much time playing World Of Goo on it and then too much time playing Sprinkle. I also have Osmos though I’d played that a fair bit on desktop.
- Having Kindle books on it is handy though the Kindle itself is a better device for reading books.
- I tried out SwiftKey X and bought it as soon as the trial expired.
- Having a small tablet for poking around the kitchen putting together a food order is one of the applications I had in mind when buying, and it doesn’t disappoint.
- Most of the photos I’ve taken recently have been through the phone. It’s been interesting watching the new MS building going up…
- I occasionally even make phone calls with it.
I’ve been posting my photo backlog to tumblr. It turns out that silly graffiti and baby cows get a lot of attention. It’s also rather easy to spend an awful lot of time browsing other people’s postings.
I’ve got the next two weeks off work.
This cartoon contains the Latin phrase “MENDACII IN CLOACA TRUCES SIDERA”. I’m trying to make some sense of it.
MENDACII is the genitive singular of mendacium, which has variety of meanings mostly amounting to “a lie”. Being in the genitive means that there is something “of the lie” or “of a lie”.
IN is a preposition with with a variety of meanings.
CLOACA is the nominative, ablative or vocative singular of cloaca, sewer.
I think the IN goes with this, making
both “in” and “into” fit.
TRUCES is the nominative, accusative or vocative plural of trux, meaning several things along the lines of “wild” or “grim”.
SIDERA is the nominative, accusative or vocative singular of sidus: constellations, stars, seasons. Being plural, TRUCES obviously modifies SIDERA rather than either of the other nouns in play.
“The sewer of the lie” makes much more sense than “The grim stars of the lie”, so I think MENDACII modifies CLOACA rather than TRUCES SIDERA.
So: “the grim stars in the sewer of the lie”? Perhaps with “the grim stars in the sewer of lies” being a more natural but less literal translation.
(Of course I may be onto a loser by assuming it’s supposed to be anything more than dog Latin in the first place…)
- The language of the Picts. Probably a Brythonic language.
- Dear Merriam-Webster. A lexicographer’s lament.
- Nearly all marine fish came from freshwater ancestors
- Sealand, HavenCo, and the Rule of Law
- Why stricter rules threaten the eurozone
- Ron was wrong, Whit is right. Sanity-checking online public keys.
Repeatedly pressing ENTER at Google Scribe:
Ducks Unlimited Canada and the United States and Canada and their territories and total client assets of approximately 1 to 4 of 4 people found the following review helpful to your business partners and customers together to participate in these features is the ability to make and use them together to make anything of it until I was introduced to them by their fruits ye shall know them by their fruits ye shall know them by their fruits ye shall know them by their fruits ye shall know them by [...]
I had a look at 38degrees and they're doing a bit more than “publishing his email address”, in fact one thing I don’t see there is an MPs email address. Rather they have a web form that pre-fills an email message to your MP (looked up by postcode) and sends it.
It looks like this:( Read more... )
The only things I entered were the email address and false name, and my postcode. Everything else is filled in by the website. I didn’t press the Send button l-)
It seems suspiciously like “push a button to spam your MP” to me and as such I can see why he’s pissed off. Perhaps they should instead send him a daily email saying how many people agreed with them (and invite anyone sufficiently motivated to say more than the boilerplate to contact him separately).
Would anyone care to argue that this sort of thing isn’t spam?