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How fast SSDs slow to a crawl: thermal throttling (2021)

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Re: How fast SSDs slow to a crawl: thermal throttling (2021)

#21
post #7

Jay has done a test regarding ssd overheating: https://youtu.be/dDTH93dgulE Verdict: once you have any kind of passive cooler on one it won’t overheat. But he has only tested it with one fast PCIe 4 x 4 drive.

Or ensuring airflow directly on the thin heatspreader already present. For my personal PC I just have a small fan inside the case perched on the backplate of the GPU blowing air directly at the NVMe slot. Very ghetto, but very effective :D

Re: How fast SSDs slow to a crawl: thermal throttling (2021)

#22

I have seen SSDs on Windows at least lose a lot of performance due to file fragmentation. While there is no particular reason why the SSD would run slow once you try to read a file from the filesystem it does slow down and it can impact performance dramatically. Dropping drive performance to 1/5 of normal after 10x of overwrites of the drive contents. The dogma at the moment is that SSDs don't require de-fragmentatio…

> The dogma at the moment is that SSDs don't require de-fragmentation

They don't require a regular de-fragmentation, like HDDs, because if you are just occasionally read some files it would be fast enough AND with a physical layer hidden by remap it doesn't make sense at all, because the file what is logically present to you as a one continuous block could be really stored across multiple locations.[0]

> I know defragging the files (copy away, delete files and replace)

And this is one the real way to "defrag" on SSD backed media. Tossing around clusters like it is a HDD only wastes your TBW.[1]

> While there is no particular reason why the SSD would run slow once you try to read a file from the filesystem it does slow down and it can impact performance dramatically

THere is always a couple of factors what affect the performance.

Where is always a question what exactly you are reading: a bazillion of those files, but do other things on the same drive at the same time.

Also while I mention MFT - some small files are stored in it entirely[2], so all the overhead is processed quickly (because in normal conditions most of the MFT is cached in memory anyway) but it should be small enough[3].

Also don't forget what if your file is 1KB the drive doesn't read 1KB from the storage. At best it reads 4KB (the default NTFS cluster size), but if your next file isn't in this block (or it is but by the time it comes to read it the cache of this block was already flushed) then you need to wait until the previous read completes. Yes, reads are fast, in theory, but again this is where IO queue, caches, NCQ starts do matter.

And last but not least: on Windows there is always a question if the antivirus software (be it built-in Defender or a 3rd-party one) is still sane or wastes your time rechecking all your already checked, static, non-executable files. Like a bazillion of jsons.

[0] and without TRIM support you can't even have even a very loose guarantee what you really cleared the block.

[1] back in the day I used this to defrag a very heavy fragmented HDDs, just Ghost it to another drive and then restore it back - all files are defraged and it takes way less time because source drive only reads, not read-write-repeat.

[2] https://superuser.com/questions/1185461/maximum-size-of-file...

[3] just checked a couple random files on my drive - cutoff is somewhere around ~700B.

Re: How fast SSDs slow to a crawl: thermal throttling (2021)

#23

I did not see any temperature measurements of the controller though in this article so the test doesn't feel very scientific to me. It's not just thermal throttling of the controller that causes slowdown, it's also the filling of the DRAM/SLC cache. Also, we should talk more about some vendors screwing over customers by replacing controllers or NAND chips with slower parts to cut down cost while keeping the same SSD…

Cf https://dl.acm.org/doi/pdf/10.1145/3064176.3064187

Re: How fast SSDs slow to a crawl: thermal throttling (2021)

#24
post #6

Earlier quoted context omitted.

Are there any programs that can track temperature for different vendors? I'd love to run a few ssds through a benchmark and have hard data for thermal data.

Temperature data is part of SAMRT so there's a plethora of utilities on any OS. For windows the best is HWInfo, IMHO. Ideally, for a proper test, I'd expect thermocouples placed on the controller and not just rely on the sensor data provided by the SSD as that could be very misleading depending on where the senor is and how the raw sensor data is processed.

arg, you are right, smart would be the easiest way to go. And the thermocouples are a great idea. I'll see what I can whip up

Re: How fast SSDs slow to a crawl: thermal throttling (2021)

#25

Earlier quoted context omitted.

Samsung was one of the vendors doing this... there was some controversy about them changing the specs on the datasheet without changing the SKU. This was for Samsung-branded drives, one of the 9xx models iirc.

Samsung did update their SKUs. Link: https://www.tomshardware.com/news/samsung-is-swapping-ssd-pa... I'd advise against throwing accusations without proof. Looking for reliable hardware vendors is hard enough, there is no need for people unintentionally muddying the waters.

The marketing name still seems to be the same according to the article, so it would still fail any reasonable consumer confusion test.

Re: How fast SSDs slow to a crawl: thermal throttling (2021)

#27

Isn't thermal throttling good? Without that safety measure you'll break your PC. I don't care if climate change kills millions of people. It impacts my summer gaming sessions. I need AC!

Yes, but you would expect that the product was designed that this downt occur in "regular" conditions. Unfortunately many products unavoidably throttle themselves. This is likely because they run cool long enough to get good reviews and benchmarks so longer performance doesn't really matter to them.

Re: How fast SSDs slow to a crawl: thermal throttling (2021)

#28

Earlier quoted context omitted.

Samsung did update their SKUs. Link: https://www.tomshardware.com/news/samsung-is-swapping-ssd-pa... I'd advise against throwing accusations without proof. Looking for reliable hardware vendors is hard enough, there is no need for people unintentionally muddying the waters.

The marketing name still seems to be the same according to the article, so it would still fail any reasonable consumer confusion test.

Have you checked the performance difference or are you just venting based on click-bait articles?

According to benchmarks, the difference in performance is negligible, in fact the new SKU is sometimes better than the old one in most benchmarks, so there's really nothing to worry about.

You're grasping at straws here.

Re: How fast SSDs slow to a crawl: thermal throttling (2021)

#29

This is well known in the industry. Just under 10 years ago, I was on a support team for 'Enterprise flash', which meant PCIe cards stuffed with NAND flash. The card sizes were 500MB to 2.2TB. One of our tasks was to help qualify supported systems, which went down to approving SOME chassis IF the card was in a particular slot with a specific airflow. In some cases, it was required that internal ribbon cables were re-…

[deleted]

Re: How fast SSDs slow to a crawl: thermal throttling (2021)

#30
Glad to see attention brought to this issue. I recently started using these:

ASUS Hyper M.2 X16 PCIe 4.0 X4 Expansion Card Supports 4 NVMe M.2 (2242/2260/2280/22110) up to 256Gbps for AMD 3rd Ryzen sTRX40, AM4 Socket and Intel VROC NVMe Raid https://www.amazon.com/dp/B084HMHGSP/ref=cm_sw_r_cp_api_i_ZY...

If you have a spare x16 slot I highly recommend. I’ve torture tested the latest and greatest hot screaming NVMe drives with it and between the massive heat sink and fan I’ve never seen NVMe temps rise above 40c.

Supporting more than one NVMe is tricky, though. You need to make sure your motherboard supports PCIe bifurcation. Common in server motherboards and some recent high end consumer motherboards but virtually unsupported with everything else. That said if you’re experiencing NVMe throttling due to temperature it’s worthwhile for even one drive.

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