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As long as computer is operating, OS constantly performs small writes to storage medium. This is what I have not paid attention to earlier until I saw total writes in CrystalDiskInfo, Intel Toolbox and writing activity in Windows 7 Resource Monitor:

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As you can see, rtvscan process which is Symantec Endpoint Protection is performing almost 1MB/s writes and is scheduled to run once every week with full system scan which I wonder whether should replace with another less-resource intensive antivirus. I am not yet knowledgeable about Host Writes, NAND Writes and difference between both, but considering I have been using SSD only for 2 weeks with mostly browsing, over 180GBs is a lot of writes.

If my assumptions are correct, I reckon just by having computer idle with OS running (which often is case with mine) will continue wearing out SSD, hence not forgetting to put machine on Standby or even Hibernation if you know you won't use computer for long will reduce unnecessary writes and prolong SSD's life.

Boris_yo
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    rtvscan actually only writes 380,715 Bytes/sec. Furthermore you are worried about nothing, ssd have an estimate lifespan of years, at a rate of something like 100GB. Place the 130GB in perspective. Break that down to he 1,334 hours. – Ramhound Sep 18 '12 at 12:33
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    I mistakenly left out the rate would be writting 100GB of data each day. If each cell was 1GB this would mean you have 120 cells. Lets say there is an addition 30% that is hidden. This means you actually have 156 cells. If you means each cell can write around 10,000,000,000,000 bytes ( 1,000,000,000 * 10,000 ). This means your typical 120GB SSD can write couple hundred TB over the lifespan of the device if my math is correct. – Ramhound Sep 18 '12 at 12:59

1 Answers1

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The main thing that shortens the life of a SSD is writing to it. Modern SSDs like yours have rather high life expectancies. The amount of write cycles a SSD can endure is not a fixed value, but manufacturers try to keep this low using various techniques. In your example, you can see that even though your computer wrote 181GB to the drive, the advanced wear-levelling technique and compression made it only write 131GB to the actual NAND (storage) cells - basically every cell on your SSD has only been written to once and some have received two writes. Typical cell endurance is between 100 (very low) and 10000 (quite good).

You will see in this article that others have put a similar SSD under a much higher workload and yet the S.M.A.R.T. data didn't even show 1 percent usage. So, effectively, if you continue to use your SSD like in the last 2 weeks for the next year, you will hit the usage rate like they tested in the article, and you won't even have used 1% of your SSD life expectancy.

Just having your SSD connected to power will also shorten the life of your SSD, but absolutely negligibly so (think 1 million times less than writing to it).

Stefan Seidel
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    Nope, sorry. Modern SSD's have worse life expectancies as their predecessors. My company buys Flash in bulk and we regularly test until failure. You may think ~10.000 writes is quite good; the Flash we bought 4 years ago survived 130.000-180.000 writes. Two important reasons are the smaller cells (~30nm nowadays) and MLC (2 bits per cell, which means two extra intermediate voltage levels) – MSalters Sep 18 '12 at 13:43
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    Consumers will still often get higher life expectancy because previous SSDs didn't perform live compression and had worse wear leveling algorithms. So for consumer use, life expectancy usually exceed that of the computer system they're installed in (unless a singular catastrophic failure happens to it). – Stefan Seidel Sep 18 '12 at 13:50
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    @StefanSeidel Thanks for explaining me the difference between host writes and NAND writes. – Boris_yo Sep 18 '12 at 14:57