Heavy Disk Write usage. ( Killing SSD )

[ksec]

Before My previous Reboot, my Activity Monitor was showing 16TB of data written in total. Kernel_task was responsible for majority of that.

TB, not GB.

That had me extremely worried, the starting date of Activity Monitor was 16 days ago according to "Sample Text". That is 800GB, more then my SSD total capacity 500GB, 1 Drive Write per day!

This is my current Stats, and this is less then 24 Hours. A total of 10GB+ Write already.

A BookmarksSyncAgent need to write 1.73GB !?
LaunchD needs write 1.41GB

What went wrong ?

 

[treekram]

Based on what you have presented, you should look at web plugins, websites, or cloud services that may be writing large amounts of data. For example, in late 2016, there was a bug (since fixed) in Spotify that resulted in large amounts of data being written.

launchd doesn't look too bad. I've had my computer on for about 8 hours now and it shows 1.66GB being written. cfprefsd is unusual - that deals with preferences and those usually don't involve large amounts of data. The SafariBookmarksSyncAgent is an iCloud thing.

If you write 20GB a day (you say that 10GB has been in under 24 hours), that would be 7.3 TB/year, which would not be an issue. Writing 500GB a day consistently would be an issue.

You can try logging out of iCloud (System Preferences) and see how that affects the data written. After that, as mentioned at the top of my post, you'd have to take a look at your specific web plugins or cloud services. Websites can write a lot of data but I don't think just browsing a website would create the problem you're having where 500GB is written in one day. Obviously if you download a lot, that could be an issue. You could also have some other app that's writing a lot of data but without any evidence of that, we can't guess if that's the case or not.

You didn't mention what Mac you have. If you have one which uses a standard SATA SSD, you might just find a way to reduce the usage somewhat and just buy something like a Samsung 860 Evo, which has endurance of 300TB for the 500GB model. If you have a Mac which uses an Apple-proprietary SSD, then you would want to do more work to reduce the SSD usage from the 500GB/day.

 

[Fishrrman]

I recall there being some apps (perhaps associated with online music services) that would write tens or hundreds of gigabytes of info to a drive while active. The amounts were enormous and totally out-of-proportion to what one would expect.

OP:

It might help if you ran EtreCheck (free download), and posted your results here.

 

[ksec]

OP:

It might help if you ran EtreCheck (free download), and posted your results here.

Will do.

Here is my latest stats since 8/8 02:00

I restarted Safari, where it was previously around 5.5GB, so in total it should now be, around 6.7GB

I have written ~70GB for the last 3 days. That is 20GB plus....

 

[sethia]

I have beenf facing similar issue. 3TB writes/read in just 10 Days and avergae of 100MB reads is strange

Will do.

Here is my latest stats since 8/8 02:00

View attachment 775282 View attachment 775283

I restarted Safari, where it was previously around 5.5GB, so in total it should now be, around 6.7GB

I have written ~70GB for the last 3 days. That is 20GB plus....

 

[ksec]

I have beenf facing similar issue. 3TB writes/read in just 10 Days and avergae of 100MB reads is strange

If the majority are Kernel task, then they are basically swap. I.e You are running out of memory.

I think Apple should default all Mac to 16GB Memory, otherwise the SSD won't last long under these sort of usage.

 

[LogicalApex]

If the majority are Kernel task, then they are basically swap. I.e You are running out of memory.

I think Apple should default all Mac to 16GB Memory, otherwise the SSD won't last long under these sort of usage.

Modern SSDs can handle a lot of writes. Endurance is measured in Drive Writes Per Day (DWPD) and although Apple doesn't publish endurance information for their SSDs I'm sure they are in line with top tier drives like Samsung Pro SSDs and can easily handle more than 5 DWPD and I highly doubt any user will write enough data to their SSD to kill it unless intentionally aiming to do so (like in the TechReport story quoted from a few years back by PC World).

https://www.pcworld.com/article/2856052/grueling-endurance-test-blows-away-ssd-durability-fears.html

 

[ksec]

Modern SSDs can handle a lot of writes. Endurance is measured in Drive Writes Per Day (DWPD) and although Apple doesn't publish endurance information for their SSDs I'm sure they are in line with top tier drives like Samsung Pro SSDs and can easily handle more than 5 DWPD and I highly doubt any user will write enough data to their SSD to kill it unless intentionally aiming to do so (like in the TechReport story quoted from a few years back by PC World).

https://www.pcworld.com/article/2856052/grueling-endurance-test-blows-away-ssd-durability-fears.html

Most modern consumer SSD don't have 5 DWPD, and even enterprise rarely hit that number. And the endurance for Samsung Pro SSD comes with TWD roughly 1000x of its original drive, i.e if it was 500GB it would have 500TB Write Endurance. And in that post the Tech Report Notes he has less than 2TB write over the span of two years. We are doing then in less than a week.

Depending on Scenario, we are on average 200GB to 400GB Write per day, on a 256GB, with ~300 TWD, that drive will last you less than 3 years. It would be better on 512GB as it it closer to 6 years.

 

[sethia]

I found out its chrome which is the Culprit but not able to identify why and how?

If the majority are Kernel task, then they are basically swap. I.e You are running out of memory.

I think Apple should default all Mac to 16GB Memory, otherwise the SSD won't last long under these sort of usage.

 

[ksec]

I found out its chrome which is the Culprit but not able to identify why and how?

May be you are having many tabs opened? I do have dozens of tabs open at the same time, if you take ~400MB Memory per tab that is 4GB+ Memory already. Once you ran out of physical memory and start doing paging, which is where the kernel task start showing up with heavy write.

 

[LogicalApex]

Most modern consumer SSD don't have 5 DWPD, and even enterprise rarely hit that number. And the endurance for Samsung Pro SSD comes with TWD roughly 1000x of its original drive, i.e if it was 500GB it would have 500TB Write Endurance. And in that post the Tech Report Notes he has less than 2TB write over the span of two years. We are doing then in less than a week.

Depending on Scenario, we are on average 200GB to 400GB Write per day, on a 256GB, with ~300 TWD, that drive will last you less than 3 years. It would be better on 512GB as it it closer to 6 years.

The Tech Crunch report that PC World was quoting had drives exceeding 2 petabytes and still being usable... Well in excess what manufacturers rated the drives for.

 

[ksec]

The Tech Crunch report that PC World was quoting had drives exceeding 2 petabytes and still being usable... Well in excess what manufacturers rated the drives for.

Ok, I will bite.

There is one, out of 6 that lasted 2 PB. Other failing before the 1PB marks. Some of them even had earlier SandForce Write Compression, i.e Actual Write Data were lower.

Those NAND were easier 2xnm MLC which has higher endurance than today's 1xnm MLC. Or TLC even. Although Apple don't use TLC in any of its Mac as far as I know up to end of 2017.

You don't want your SSD to be actually "dead". Your Data will be non recoverable.

On a 256GB SSD, which is the entry level for MacBook Pro, a 300GB Write per day will barely last you 3 years under designed warranty condition, and anything more you are at risk.

The same paging problem does not exist on Windows or Linux even. And one reason why many claims SSD aren't a problem in normal usage. Except this is not the case on macOS.

Even if we ignore Paging from Kernel, SafariBookMarkSync has managed to wrote 6GB of Data in the past 10 Days. 6GB for just Bookmarks.

 

[sethia]

yes that seems to be the case but if it wears out my SSD, should I stop browsing more tabs? This is strange and as others are pointing out the SSD life would be 3 years only then

May be you are having many tabs opened? I do have dozens of tabs open at the same time, if you take ~400MB Memory per tab that is 4GB+ Memory already. Once you ran out of physical memory and start doing paging, which is where the kernel task start showing up with heavy write.

 

[ksec]

yes that seems to be the case but if it wears out my SSD, should I stop browsing more tabs? This is strange and as others are pointing out the SSD life would be 3 years only then

It depends. I want to note that Tab Overview in Safari is especially bad in this. It doesn't just show the Tab Thumbnail in the overview, it actually loads the WebSite in Background. For those who are heavy on Tabs with over 100 Tabs opened, this could easily be 400GB using just the Tab Overview Function.

As I have pointed out, it is the warranty that is 3 years only. It will likely last longer if you are comfortable with it.

My suggestions is switch to Firefox, which has option to allow only set amount of Tab concurrently loaded, it should reduce the load by quite a lot.

 

[sethia]

I think by now I have burned/lost 2 SSDs due this memory issue, onto my 3rd and the speed at which its being used it won't last more than a year. Even started using Brave but seems the same issue.

Surprised neither Chrome not Mac teams are fixing this, The M1 Swap issues were related to this I think

 

[boswald]

It depends. I want to note that Tab Overview in Safari is especially bad in this. It doesn't just show the Tab Thumbnail in the overview, it actually loads the WebSite in Background. For those who are heavy on Tabs with over 100 Tabs opened, this could easily be 400GB using just the Tab Overview Function.

As I have pointed out, it is the warranty that is 3 years only. It will likely last longer if you are comfortable with it.

My suggestions is switch to Firefox, which has option to allow only set amount of Tab concurrently loaded, it should reduce the load by quite a lot.

Other than switching browsers, is there a way to disable Tab Overview?

 

[ksec]

Other than switching browsers, is there a way to disable Tab Overview?

You cant really "disable" per se but you can stop using it. I did two modification with Safari. ( The way Safari is heading I might switch back to Firefox soon )

1. Disable Zoom in Zoom Out with Two Fingers ( I think ) in System Preference > Trackpad. The Zoom in Zoom out is a short cut gesture in Safari for zooming out to Tab Overview. Which I happen to accidentally doing it from time to time.

2. You can, as of Safari 14 remove the Tab Overview icon from your Tab Bar. This way you wont mis-click it again.

Ever since then my Disk usage has been manageable. Now doing roughly 50GB/ day. ( 50GB/ day is still unhealthy but at least manageable )

I think by now I have burned/lost 2 SSDs due this memory issue, onto my 3rd and the speed at which its being used it won't last more than a year. Even started using Brave but seems the same issue.

Surprised neither Chrome not Mac teams are fixing this, The M1 Swap issues were related to this I think

On Chrome there are certain options or extension that unload Tabs from memory usage after it is sitting in idle. ( I even believe they made it as default in the recent chrome version ). That way even if you have hundreds of tabs they are not really loaded but more like a reading list.

You may want to try Firefox as well.

 

[jav6454]

Is this an M1 Mac or Intel?

 

[ksec]

Is this an M1 Mac or Intel?

Intel, the start of the thread was from 2018. I have been saying in every M1 thread, high disk write isn't a new thing on macOS.

 

[MarkC426]

Give us more system specs.....
How much ram, which OS?

Sounds like you don't have enough ram.

I have been using a Samsung 840 evo for 7 years, and it still shows 99% life remaining.

 

[boswald]

You cant really "disable" per se but you can stop using it. I did two modification with Safari. ( The way Safari is heading I might switch back to Firefox soon )

1. Disable Zoom in Zoom Out with Two Fingers ( I think ) in System Preference > Trackpad. The Zoom in Zoom out is a short cut gesture in Safari for zooming out to Tab Overview. Which I happen to accidentally doing it from time to time.

2. You can, as of Safari 14 remove the Tab Overview icon from your Tab Bar. This way you wont mis-click it again.

Ever since then my Disk usage has been manageable. Now doing roughly 50GB/ day. ( 50GB/ day is still unhealthy but at least manageable )



On Chrome there are certain options or extension that unload Tabs from memory usage after it is sitting in idle. ( I even believe they made it as default in the recent chrome version ). That way even if you have hundreds of tabs they are not really loaded but more like a reading list.

You may want to try Firefox as well.

Thank you for the tips! I don’t have a trackpad, but I have zooming disabled within Mouse settings.

 

[ksec]

For the sake of testing I just did Tab Overview with 200 Tabs, burned through nearly 500GB disk write....

 

[MarkC426]

What is it with Safari (or other web browsers) using so much system resources.
It's just a bunch of web data....

When you compare with a high end graphic/video app, which uses knowhere near...... 🤪

 

[sethia]

Have an 8GB Mac, Retina Pro 2013/14 model, now with 256 GB SSD disk space

I run between 45-250 tabs across browsers (Chrome/Brave), starting to use Firefox as well

But don't think this is going to improve

The disk in its worst time writes like 3TBs in a week easily.

Majority attributed to kernel_task

PC runs usually at 6 GB memory used out of 8 and Cached and Swap show like 4-5 GBs additional.
Memory pressure remains green but in between surged to yellow and red slowing down the PC when more applications open.

Using Chrome extensions as well 5-6 of them,

It appears Mac has some mismanagement here allow SWAP to eat up the hardware! But they are not taking responsibility and pinning it on Chrome for low-quality leaky code!

 

[MarkC426]

I run between 45-250 tabs across browsers (Chrome/Brave)

Whaaaaaaaaaat.....

Holy Moly, I only ever have 3-4 tabs (on my iPad).