RE: [gentoo-user] Synchronous writes over the network.

[Laurence Perkins <lperkins@openeye.net>]

>> -----Original Message-----
>> From: Rich Freeman <rich0@gentoo.org> 
>> Sent: Thursday, December 23, 2021 9:50 AM
>> To: gentoo-user@lists.gentoo.org
>> Subject: Re: [gentoo-user] Synchronous writes over the network.
>> 
>> On Thu, Dec 23, 2021 at 12:39 PM Mark Knecht <markknecht@gmail.com> wrote:
>> >
>> > I'll respond to Rich's points in a bit but on this point I think 
>> > you're both right - new SSDs are very very reliable and I'm not overly 
>> > worried, but it seems a given that forcing more and more writes to an 
>> > SSD has to up the probability of a failure at some point. Zero writes 
>> > is almost no chance of failure, trillions of writes eventually wears 
>> > something out.
>> >
>> 
>> Every SSD has a rating for total writes.  This varies and the ones that cost more will get more writes (often significantly more), and wear pattern matters a great deal.  Chia fortunately seems to have died off pretty quickly but there is still a ton of data from those who were speculating on it, and they were buying high end SSDs and treating them as expendable resources - and plotting Chia is actually a fairly ideal use case as you write a few hundred GB and then you trim it all when you're done, so the entirety of the drive is getting turned over regularly.  People plotting Chia were literally going through cases of high-end SSDs due to write wear, running them until failure in a matter of weeks.
>> 
>> Obviously if you just write something and read it back constantly then wear isn't an issue.
>> 
>> Just googled the Samsung Evo 870 and they're rated to 600x their capacity in writes, for example.  If you write 600TB to the 1TB version of the drive, then it is likely to fail on you not too long after.
>> 
>> Sure, it is a lot better than it used to be, and for typical use cases I agree that they last longer than spinning disks.  However, a ZIL is not a "typical use case" as such things are measured.
>> 
>> --
>> Rich
>> 
>> 

This is also why the video surveillance industry still uses spinning rust for anything beyond a very minimal capacity.  

Rotating drives wear out primarily based on time run as long as you're not thrashing the heads all the time by running Windows (Windows 10 seems to have given up even trying to optimize read and write on non-SSD media.)

SSD wears out primarily based on write throughput, and anything with a large turnover can easily wear one out in a matter of months.

LMP