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

I did not see any temperature measurements of the controller though in this article so the test doesn&#x27;t feel very scientific to me.<p>It&#x27;s not just thermal throttling of the controller that causes slowdown, it&#x27;s also the filling of the DRAM&#x2F;SLC cache.<p>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 SKU, after seeding the original SKUs to reviewers to lock in good benchmark scores in online tests. This is why I recommend only buying SSDs from reputable vendors&#x2F;OEMs who are more vertically integrated: Samsung, WD, Sandisk, Micron.

It is strange for it to attributed to thermal throttling when there are no measurements taken and not even a simple correlative graph to demonstrate the relationship. I&#x27;m sure it definitely could be the case though, just a comment on the strange assumption the article seems to take.<p>With no research what-so-ever I would have attributed the slow down to some kind of cache or buffer filling up.

Glad to see attention brought to this issue. I recently started using these:<p>ASUS Hyper M.2 X16 PCIe 4.0 X4 Expansion Card Supports 4 NVMe M.2 (2242&#x2F;2260&#x2F;2280&#x2F;22110) up to 256Gbps for AMD 3rd Ryzen sTRX40, AM4 Socket and Intel VROC NVMe Raid <a href="https:&#x2F;&#x2F;www.amazon.com&#x2F;dp&#x2F;B084HMHGSP&#x2F;ref=cm_sw_r_cp_api_i_ZYAPX8XMGCVBJ6B05YM0?_encoding=UTF8&amp;psc=1" rel="nofollow">https:&#x2F;&#x2F;www.amazon.com&#x2F;dp&#x2F;B084HMHGSP&#x2F;ref=cm_sw_r_cp_api_i_ZY...</a><p>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.<p>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.

This is well known in the industry. Just under 10 years ago, I was on a support team for &#x27;Enterprise flash&#x27;, which meant PCIe cards stuffed with NAND flash. The card sizes were 500MB to 2.2TB.<p>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-routed to improve airflow. The flash cards would throttle progressively at set temperatures, eventually going read-only and offline to protect the contents.<p>The issue of temperature and thermal throttling carried-on into the &#x27;consumer&#x27; HDD replacement market. I can recall attending an online tech briefing on SSDs where I put a comment in the chat that one issue not being covered was device temperature. When this was put to the panel of &#x27;experts&#x27;, they were a bit bemused, commenting that SSDs don&#x27;t get hot because they consume less power than HDDs. Environmental conditons were not even considered.<p>Truth is that, with a bit of averaging, the power consumption of a modern 2TB HDD is about the same as a 2TB SSD: around 2-5W. Both devices generate heat and both devices are often in a warm environment.

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&#x2F;5 of normal after 10x of overwrites of the drive contents.<p>The dogma at the moment is that SSDs don&#x27;t require de-fragmentation and that is potentially true to a certain point but I think Windows actually needs the file system de-fragmented due to its overhead. I have a program to reproduce the effect and have been meaning to test EXT4 and write an article about it at some point. I need to check its something that happens across a range of devices before I publish and it really is just windows, I know defragging the files (copy away, delete files and replace) works to instantly fix performance but it could be device&#x2F;controller&#x2F;firmware specific.<p>The other possibility is large amounts of writes filling the device can result in reduced working space especially in drives with very small amounts of cache that cause slow downs near the end of tests.

With all the respect to the author, any experiment should be reproduced. More than 1 disk should be tested, the temperature should be measured, and a comparison to the externally cooled disk would be looking great here. Without that, we just have some assumptions, that are partially (or fully) correct (or incorrect).

Jay has done a test regarding ssd overheating: <a href="https:&#x2F;&#x2F;youtu.be&#x2F;dDTH93dgulE" rel="nofollow">https:&#x2F;&#x2F;youtu.be&#x2F;dDTH93dgulE</a><p>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.

The irony is that flash write endurance for modern flash chips is actually greater if the writes are at higher temperature. Charge mobility is greater, and the writing damages the cells less.<p>Unpowered persistence is the opposite, however. At 85 Celsius, the data may last only single digit days unpowered by at freezing temperatures could last hundreds of years unpowered. For the same reason, I believe: charge mobility is lower at lower temperatures in semiconductors.

I wonder if this is what permanently effected a 256GB Adata SATA SSD I had in my Linux box. I was running updates and noticed it was very slow once it started unpacking everything. At first I let it go and went about my business surfing the web which wasn&#x27;t hitting the disk. Finished updating, decided to reboot as new kernel was pulled and the issue was now obvious as it was dragging its feet booting. Worried, I ran a backup of my home dir upon login and every file transfer topped out at 4 or 5 MB&#x2F;sec. SMART was enabled but reported nothing.<p>I wound up dumping the ssd to ensure I had a full image and that entire operation topped out at 5 MB&#x2F;s. And I had the SSD out of the case in a cradle when ripping so it wasn&#x27;t getting cooked in the case. I did not notice it feeling abnormally warm or hot. I later tried to mess with the disk in a cradle but as soon as I powered it on it topped out at 4-5 MB&#x2F;sec so either there is some sort of defect causing an immediate thermal issue or something in the controller went awry.

It had never even occurred to me that my <i>storage</i> would want cooling, until I swapped in a new motherboard, moving from atx to mini-itx, and I noticed that the nvme.2 socket was covered by a heat sink. Performance is literally 50% better - and it still gets toasty.

Isn&#x27;t thermal throttling good? Without that safety measure you&#x27;ll break your PC.<p>I don&#x27;t care if climate change kills millions of people. It impacts my summer gaming sessions. I need AC!

I have experienced this with using m.2 SSDs in an external enclosure. I found they all throttled until I bought one that had a fan. Never throttled again.