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ssd swap - high usage of Terabytes Written
- Thread starter Forti
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Thank you for the great post. I am still very frustrated by huge SSD writes when using Lightroom Classic on M1s. Especially the Develop module. And unfortunately there is not much help over in the Adobe forums. Can anyone here provide some tips as to how to better manage usage in Lightroom Classic until Adobe finally gives us an M1 version that does a better job managing swapping?To anyone interested and affected by excessive SSD writes on M1, I've posted my list of fixes for excessive SSD writes on the first page of this thread, as well as here where I was able to attach relevant screenshots.
I expect most people to be able to fix their excessive SSD writing by trying these steps, atleast until Apple fixes it themselves.
Definitely switching from Safari to using Brave with Auto Tab Discard - as I do a lot of intensive browsing for software development (I regularly have 50+ tabs open at once), using Safari while having all my other apps open would cause Safari Web Content (Cached) to be written to SSD swap memory like crazy. Additionally, as all Safari tabs were more or less kept in memory (even if I closed them or didn’t use them for long periods of time), this in itself put immense pressure on my 8GB of RAM and my kernel_task writes were regularly reaching 400GB+ in a single day after just doing what I consider to be my normal workflow.
Even people who only do light/moderate browsing can be affected by this if they have a lot of apps open, hence why I think switching from Safari is the best first step to try if you’re affected by high SSD writes.
If Apple were to allow users to turn off the website caching, as well as implementing the option of old open tabs to be discarded from memory after a period of time, then Safari would not be an issue for people in a similar situation to me.
That all being said, a lot of people are using Safari and not having writing issues in which case, keep using it
it’s a great browser for every reason other than the issues it causes for some.
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Thanks! I mainly use Firefox for general browsing and Safari for finances only (which are closed immediately after use).Definitely switching from Safari to using Brave with Auto Tab Discard - as I do a lot of intensive browsing for software development (I regularly have 50+ tabs open at once), using Safari while having all my other apps open would cause Safari Web Content (Cached) to be written to SSD swap memory like crazy. Additionally, as all Safari tabs were more or less kept in memory (even if I closed them or didn’t use them for long periods of time), this in itself put immense pressure on my 8GB of RAM and my kernel_task writes were regularly reaching 400GB+ in a single day after just doing what I consider to be my normal workflow.
Even people who only do light/moderate browsing can be affected by this if they have a lot of apps open, hence why I think switching from Safari is the best first step to try if you’re affected by high SSD writes.
If Apple were to allow users to turn off the website caching, as well as implementing the option of old open tabs to be discarded from memory after a period of time, then Safari would not be an issue for people in a similar situation to me.
That all being said, a lot of people are using Safari and not having writing issues in which case, keep using it
OK, apparently swap is almost not used, but to be precise the output of the vm_stat from the shell would help.
Before 11.4beta, I observed severe anomalies starting from the swap size ca 5Gb or higher.
Browsers as very intense memory users, trigger unnecessary swap writes easier than other processes, when swap use is already high.
Awesome, thanks! I think for most the writes start around 4GB Swap.
For me it was almost "normal" with 70 tabs open, at 100 it was writing like crazy (in Safari). Can you try opening a bunch more tabs to see what happens?
I hadn't really tested this in Chrome, I switched over to Safari when I got the M1. When I switched to Firefox a few weeks ago it wrote 300GB in under an hour until I installed the Auto Tab Discard addon.
I just tried opening 140 random (all different) tabs in Chrome and I started seeing the writes increase (10GB swap, 60GB writes in 1 hour). It doesn't really look to me like your AliExpress pages are using all that much ram (more than a typical page, but not super high). Plus, Chrome might be conserving memory since all those pages share a lot of graphics and such. In my Activity monitor, some of my Chrome pages (Google Chrome Helper (Renderer)) are over 500MB, though some of them are below 50MB. You may need to open another 100+ AliExpress pages to see it kick in.
Here is my current biggest ram eater page (video stream + live chat): -https://www.youtube.com/watch?v=sTA0GTgFn5E
Some other sites that I have seen eat up ram are Discord, Slack, Facebook, various news sites (CNN, New York Times, etc), and others that I closed when this all started (live fire/earthquake maps and such that I no longer keep open).
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I concur 100%. Since moving from Safari to Edge with auto-tab-discard my disk writes have reduced at least five-fold to a much more reasonable 50-100GB / day.Definitely switching from Safari to using Brave with Auto Tab Discard - as I do a lot of intensive browsing for software development (I regularly have 50+ tabs open at once), using Safari while having all my other apps open would cause Safari Web Content (Cached) to be written to SSD swap memory like crazy. Additionally, as all Safari tabs were more or less kept in memory (even if I closed them or didn’t use them for long periods of time), this in itself put immense pressure on my 8GB of RAM and my kernel_task writes were regularly reaching 400GB+ in a single day after just doing what I consider to be my normal workflow.
Even people who only do light/moderate browsing can be affected by this if they have a lot of apps open, hence why I think switching from Safari is the best first step to try if you’re affected by high SSD writes.
If Apple were to allow users to turn off the website caching, as well as implementing the option of old open tabs to be discarded from memory after a period of time, then Safari would not be an issue for people in a similar situation to me.
That all being said, a lot of people are using Safari and not having writing issues in which case, keep using it
Overall memory usage seems to be a lot less, even with 50-80 tabs open.
I haven't installed it yet, but reports from the beta were that there were some improvements. Bigger improvements in 11.4 beta.
I did another test with Safari. 50 pages but this time different ones. I included a lot of news sites, YouTube, Google Maps, Bing Maps, Facebook. For the screenshot I additionally opened the vm_stat this time. Memory pressure is higher than Chrome (Safari has always been using more RAM for me) but still far from using any large junks of swap.
Power cycles here means power-on-cycles of the SSD (how often it was powered on). That has nothing to do with the battery. The SSD gets powered down even during use when not accessed for a certain amount of time. It also is powered down when your Mac goes to sleep. "High" amounts of power cycles on the SSD are not uncommon.
I will try that later but that definitely isn't a normal usage scenario. Whatever is going on with the machines that write on the SSD like crazy, something is very wrong with them.
Since all the SMART data from smartmontools on an M1 comes from the SSD controller designed by Apple and all the data is coming from Apple APIs, it is as accurate as Apple made it. I think you can assume the values are correct.
I don’t know about Drive DX because I don’t think their software is open source. But I’ve looked at smartmontools which is open source and their code is correct. I’ve verified it by writing my own version which uses slightly different Apple APIs and the results match exactly.
Here you go, 100 Safari tabs. And yes, it does start using the swap file with 1.18GB. But I still wouldn't call the writes excessive. Doing the same with Chrome uses 0.32GB of Swap. More importantly, I tested the same on a Hackintosh Mini PC with 16GB of RAM. The behavior is identical. So nothing unusual going on there with the M1. Neither does the M1 use less RAM or Swap nor does it use more than an x86 machine.
I can also report, I am now on 11.3. I have my usual 65+ Tabs Open. For the first time since I have owned this machine, Swap is at 0!!!
I don't think this issue is necessarily limited to M1 Macs. I have noticed this both on my M1 MBP and on my Intel 2019 MBP.
Following the update to macOS 11.3, kernel_task has written over 4.5 TB within a day (!) on the 2019 MBP and is currently writing at a rate of ca. 200-250 GB/hour with no obvious culprits (I'm running Edge with about ten tabs, OneNote, Spark, Bear and nothing else special at the moment). 1 TB written in a little less than 3 hrs now on an Intel MBP. 🤷♂️
Following the update to macOS 11.3, kernel_task has written over 4.5 TB within a day (!) on the 2019 MBP and is currently writing at a rate of ca. 200-250 GB/hour with no obvious culprits (I'm running Edge with about ten tabs, OneNote, Spark, Bear and nothing else special at the moment). 1 TB written in a little less than 3 hrs now on an Intel MBP. 🤷♂️
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No, you are wrong. All kinds of users have this issue (or not). The use case does not seem to matter. That's why nobody figured out the cause yet.
This is a little disheartening, as I was originally writing roughly 1TB/day, then utilizing the methods in the Wiki went down to 50GB/day, and now after the update to 11.3 (and no other changes) my Swap has gone down by 90% and my TBW is down to 10GB/day.