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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)

#11

Post by yair99dd »

jagermo wrote: post #6
ChuckNorris89 wrote: post #3

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…

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.

openhardwareMonitor https://openhardwaremonitor.org/ I'm windows

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

#12

Post by ChuckNorris89 »

jagermo wrote: post #6
ChuckNorris89 wrote: post #3

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…

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.

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

#13

Post by Scaevolus »

PaulKeeble wrote: post #10

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 effect of fragmentation can be estimated from the standard I/O tests-- just compare "sequential read" to "64KB random read".

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

#14

Post by 0-_-0 »

ChuckNorris89 wrote: post #3

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…

The tested SSD indeed has an SLC cache which likely filled and the author misinterpreted the cause of the throttling as thermal.

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

#15

Post by ChuckNorris89 »

madaxe_again wrote: post #8

It had never even occurred to me that my storage 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.

>It had never even occurred to me that my storage

Technically, the storage medium itself doesn't require cooling (the NAND flash chips). The issue is NAND does not exist in a vacuum on its own, as far as computer storage goes, but the SSD needs a controller to manage the data I/O from the PCI-Express bus across all the NAND chips and also caching to DRAM/SLC in between while doing various integrity, error checks and trimming in the background, so those controllers need to be very powerful for the insane speeds the PCI-E bus is capable of, being usually multi core ARM chips running a real-time OS with complex algorithms, so of course they run hot when you push them hard.

Hard disks also had controllers to manage the transfer of data between IDE/SATA to the DRAM cache and then finally the spinning rust, but since the speeds were s much slower, those controllers didn't run as hot. However, some HDDs still benefited from cooling as they had a powerful motor spinning at over 10K RPM which made the drives hot.

In either case, there's no free lunch, when you push lots of current through electronics chasing extreme performance, you get lots of heat that needs to get dissipated somehow, simple as that.

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

#16

Post by linker3000 »

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-routed to improve airflow. The flash cards would throttle progressively at set temperatures, eventually going read-only and offline to protect the contents.

The issue of temperature and thermal throttling carried-on into the 'consumer' 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 'experts', they were a bit bemused, commenting that SSDs don't get hot because they consume less power than HDDs. Environmental conditons were not even considered.

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.

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

#17

Post by the_pwner224 »

ChuckNorris89 wrote: post #3

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…

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.

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

#18

Post by shaky-carrousel »

the_pwner224 wrote: post #17
ChuckNorris89 wrote: post #3

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…

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.

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

#19

Post by justsomehnguy »

EugeneOZ wrote: post #4

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).

And the test should include something more substantial than

> a series of 96 files ranging in size from 2 MB to 2 GB, fixed sizes but in a randomised order. The test completed in a total write time of 24.4 seconds

2MB to 2GB was a good test somewhere in the early '00, not today, when even your average not-very-AAA game requires 50GB for the install alone.

Edit: and the first two graphs uses 10^8 as the base while the last one uses 10^10 for bytes, while the cumulative total says it was only 3 GB total data written.

This is not a test, it is just a bunch of loosely related data based on one "test".

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