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ssd swap - high usage of Terabytes Written
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My 500GB SSD is showing 15.1TB written, and is still on 0% used.
In my experience a lot of the writes are simply a function of having significant swap usage. The effect appears to be more noticeable with over about 5GB swap in use. Safari seems to be the biggest culprit, and I am interested in the possibility that changing browser (and disabling cache) could be a way of reducing memory usage.
On a busy day (when I have a lot of necessary tabs open) I can see up to 500GB written per day. If I take a conservative approach and shut tabs and apps down when not using them, then it can be as low as 50GB per day.
OK. I'm 900GB away from that number on my 500GB SSD so I'll see what happens. What SSD size are you running this test on?I've got good news for both of you (and all)........1% is 16TBW.......NOW recompute!
[Update: just saw that @leons is using a 256GB SSD. So maybe I would see 1% at 32TBW?]
A little digging on the old internets and I found a twitter post by Dan Moren showing smartctl output at 17.7 TBW showing 1% on a 256 GB SSD. So at least by those numbers from someone known to be knowledgeable and reliable, it appears you are correct. Thanks.
https://twitter.com/dmoren/
Yes, & BTW, my numbers and percentages are not coming from ANY tool. They are system SMART values being diretly extracted. I don't believe that Apple falsified (or allowed such) the SMART values on the drive, or there would be a class-action suit of epic proportions and we will all be rich!
The smartmontools are also extracted from SMART values from the drive controller. I've looked at the smartmontools code since it is open source. It is pretty easy to see the values come from an Apple library. The extracted block of data is not documented by Apple but the NVMe spec is available and matches the values in the byte array. So if the % used value isn't correct, that is on Apple for either not estimating correctly or for not following the NVMe specification. I've verified to my satisfaction that the actual TBW values are being correctly reported at least for my use.Yes, & BTW, my numbers and percentages are not coming from ANY tool. They are system SMART values being diretly extracted. I don't believe that Apple falsified (or allowed such) the SMART values on the drive, or there would be a class-action suit of epic proportions and we will all be rich!
The fact that
The fact that Apple has been silent on this is actually comforting. If the numbers WERE incorrect, with the many people and postings complaining about this, Apple's lawyers would never let them ignore the issue, as it would increase their liability and culpability in a future lawsuit.
Around 10-15 when I'm doing research and additional tabs for youtube.
My SWAP usage is typically < 200 MB when using Safari on my workload. I see around 20 GB written daily on top of everything else I do which is perfectly fine with me. Granted, I am only a student and not doing anything too intensive compared to most users here!
Sounds good. Those of us in the 20-50+ Tab Camp will have to wait for one of our kind to bravely try out beta 5.
Yeah, I imagine that most will also have some sort of pro apps they may use on top of Safari (or whatever browser) as well. I only use Word and FCP when I need to do edits on videos (usually 4k).Sounds good. Those of us in the 20-50+ Tab Camp will have to wait for one of our kind to bravely try out beta 5.
I just never liked having too many tabs as I get a little anxious about having that many tabs lol.
Hello. This is my first post here. I've got a 16GB Macbook M1 three days ago and I've been reading this thread carefully. A huge thanks to the whole community (and especially to leons and TheSynchronizer) for the useful advices!
There's one thing which isn't clear for me - what is a "good" amount of swapped memory? And how many GB "should" I write on a daily basis?
I noticed when running some games on Parallels (while keeping Firefox open on the Mac side) I'm getting 1-2GB of swapped memory. Is this "too much"?
There's one thing which isn't clear for me - what is a "good" amount of swapped memory? And how many GB "should" I write on a daily basis?
I noticed when running some games on Parallels (while keeping Firefox open on the Mac side) I'm getting 1-2GB of swapped memory. Is this "too much"?
Most of the time only 1. There are times where I have 2 tabs going, but not too often.
There is no "should". At the beginning of your day, run Activity Monitor. Select the Disk Tab, and write down the "Data Written" number on the bottom right. Don't reboot your computer between readings. 24 hours later, do the same, do the math, and report back (assuming it is a "typical day", otherwise, do it again). Let us know
Swap itself, or the size of it, aren’t in themselves the issue here. A high frequency of swap in/outs are the main contributors to excessive SSD writes, so they are somewhat linked but regardless not that useful.
Do as leons says above and you’ll be able to calculate your SSD writes over a ‘typical’ 24 hour period. This will give you your average x GB/hour written to the disk with normal usage.
In my opinion 5GB/hour SSD writes and below are perfectly healthy and nothing to worry about. Writes above that could lead to higher SSD wear/shorter SSD life, however, I bold the could because as we’re gradually discovering here the (256GB) SSDs in these M1 systems might have manufacturers ratings potentially as high as 1600TBW+.
Ofcourse, I prefer being safe rather than sorry, especially when I’m using my system as intensively as I want to and maintaining much lower writes at the same time, so I lose nothing for being on the safe side. But there is a possibility that these M1’s are using insanely high quality SSDs with durability such that none of our disk life concerns are legitimate.
Only time will tell
That gives 1600 TBW for 100% for the medium. The range is a ridiculous 3265 (0.5%) on the high end and 1067 (1.4999...) on the low end. That is an insane margin of error.I've got good news for both of you (and all)........1% is 16TBW.......NOW recompute!
Even given the margin of error, I'll take the 100% on the low side! and not complain!
Thanks for answer.
Did u use any other cloud software with m1 mac? Now i will try icloud but it's a little bit slow in my opinion and there is no actual setting for "store my files on mac".
Now it's a new day. Without onedrive (using icloud now) and also without safari (using firefox now).
First of all startup write reduced %50 by so far.
I will inform end of the day.
First of all startup write reduced %50 by so far.
I will inform end of the day.