SSD with a HDD installed not being trimmed automatically, why?

f14tomcat · 23 Sep 2019

Compumind said:

Yes, some clarification is in order. I had it the other way, oops!

Garbage Collection is run at idle, then TRIM will be invoked by the OS when/if scheduled.

Using TRIM, an SSD is not forced to save pages belonging to deleted files. TRIM is not an alternative to garbage collection.
It is a bit different. It actually works closely with the SSD's garbage collection algorithm to more properly mark those pages as "stale."
Now, you don’t need TRIM for garbage collection to work but TRIM makes an SSD’s built-in garbage collection routine much more efficient.

That's it. Now, breakfast.

Yep! That's basically it. Just like the article explained. Enjoy breakfast.

Compumind · 23 Sep 2019

One more thing...

Always buy a larger SSD than the amount that you will actually need.
The MTBF will be longer as the controller has more empty cells to reallocate.

Garbage Collection will still run the same way, as will TRIM when invoked.

FWIW.

f14tomcat · 23 Sep 2019

And you can over-provision the spares. Out of sight, untouchable.

Compumind · 23 Sep 2019

f14tomcat said:

And you can over-provision the spares. Out of sight, untouchable.

With modern SSD's it is not really necessary. The embedded controller (depending on manufacturer) automatically sets spares aside.
I don't do it anymore but the magic number for OP is about 10% of total unformatted capacity.

BTW - here's a good website to read...

SSD Controllers | The SSD Guy

Enjoy,

f14tomcat · 23 Sep 2019

Compumind said:

With modern SSD's it is not really necessary. The embedded controller (depending on manufacturer) automatically sets spares aside.
I don't do it anymore but the magic number is about 10% of total unformatted capacity.

BTW - here's a good website to read...

SSD Controllers | The SSD Guy

Enjoy,

Just pointing out you could, if you wanted to. Not debating the need.

Compumind · 23 Sep 2019

Have you ever done a RAID Array with SSD's?

That's fun! Blow's the HDD away...

W10 Tweaker · 23 Sep 2019

- - - Updated - - -

I've been reading endless articles on this topic and have now realized the subject is considerably more complicated than it first appeared. Many people are reporting that scheduled Trim does not occur according to the scheduled frequency ie weekly or monthly, sometimes happens monthly, but mostly does not run without manual intervention. Is this suggesting that Windows has decided that a Trim activity is not required?

I've learned that the process of trim is initiated somewhat differently with NVMe versus Sata SSD's and that Garbage Collection (GC) is a function of the SSD, not the OS.

One question... If the OS automatically sends a Trim command to the SSD (via ATA or DSM) as part of a file deletion process, why is it necessary to manually Trim or schedule Trim to run?

I still don't understand why the small partition on my SSD was automatically Trimmed while the larger partition containing my OS was NOT trimmed. Other individuals seem to have been reporting similar irregularities with scheduled Trim activities.

BTW, thanks for everyone's input.

Compumind · 23 Sep 2019

@W10 Tweaker -

In today's SSD environment, it is up to the controller and it's respective firmware to initiate Garbage Collection and if TRIM is not performed within the algorithm's parameters, to force it in conjunction with the OS.
I run all mine manually, so I make sure that it gets done. That's where in Defragment and Optimize Drives, you have the ability to schedule.

Garbage Collection is automatic. Think of it as "Fuzzy Logic" - However, if you want a TRIM, manually force it.
(In a SSD RAID configuration, TRIM can be enabled, but still not be supported by the array.)

The OS is in charge when you decide to do it manually.

Hope this helps!

W10 Tweaker · 24 Sep 2019

This has been an informative thread and thanks for everyone's contributions. I still haven't learned why my SSD is not optimized on the schedule I set in the defrag utility.

I have some 'new to me' information to share about Windows. I will present these items as factual as I now believe that to be the case but as always, I'm interested to hear if someone has a different understanding.

The defrag/optimize schedule within windows can be set to daily, weekly or monthly. This setting has little bearing on the actual defrag/optimize activity beyond this is the frequency that Windows uses to verify the disk state. It looks at the disk, decides it appears OK, won't look again until next day/week/or month. Maybe it should be renamed verification frequency.

Windows will not run a defrag/optimize activity unless specific parameters are met, I'm not privy to all of these parameters although in the links below I did find a reference to an SSD at 11% fragmented as a trigger. On average (stats from ms development group) this period is 28 days and may vary more or less.

It does appear that after 28 days +/- the utility will defrag/optimize regardless of disk state. This 28 days +/- should be taken with a grain of salt, I suspect.

Here are some references;

Don’t Waste Time Optimizing Your SSD, Windows Knows What Its Doing

The real and complete story - Does Windows defragment your SSD? - Scott Hanselman
BTW, the blog that follows this article is enlightening if you have the time.

Why should we periodically run defrag/optimize activities?

Apparently the trim commands sent by windows when a file is deleted is via an asynchronous data stream to a limited sized cache within the SSD. Some of these trim commands may be lost which could impact the efficiency of the SSD and possibly promote a condition known as write amplification.

This is the specific purpose behind periodic Trim commands created during an optimize disk activity.

My background is hardware-related and I'm new to Windows 10. Please try to be constructive with any critique. Thanks

Compumind · 24 Sep 2019

W10 Tweaker said:

This has been an informative thread and thanks for everyone's contributions. I still haven't learned why my SSD is not optimized on the schedule I set in the defrag utility. l

It should. Perhaps there is a bug or corruption. Have you tried looking at the Task Scheduler?

Now, a few questions -

1) Who is the manufacturer of your SSD? They might be the best source to answer some of your new questions.

2) It is interesting to note your interest/comment of Write Amplification. Therefore, here is a downloadable PDF that might answer many of your questions: Internal Error (Ignore the URL error.)

3) TRIM Performance Testing in Windows 10: https://docs.microsoft.com/en-us/win...1-2878d4fec369

Hope this helps you isolate the problem. I wish that I was in front of your system.

Please post back if you find the answer to the scheduling.