Are DRAM Less drives really such slow junk?

[_roman_]

I really wonder if those DRAM less drives are really such garbage. Just below my real life scenario. Mixed files. My gentoo installation from 2006 has a lot of small files.
I'm not sure how the linux kernel from a livecd handles dram less drives. 4 Minutes instead of 5 Minutes Backup time for more data is really an impressive improvement.

I made a backup of my gnu gentoo linux on the 3rd of december 2024. Th drive is a KC3000 2tb -> with LVM2 -> with luks encryption -> BTRFS filesystem with file compression
The Destination is an external usb nvme bridge with a DRAM less WD SN570 1TB

When i calculated correct 5 minutes 20 seconds (the previous backups had similar times)

First lines show the start and end of the backup procedure. End is determined after the files were succesfully flushed to the disc
df command just shows the size of 89G

Sienna_Cichlid /home/roman # cat /mnt/backup_03_12_2024/start /mnt/backup_03_12_2024/end
Tue Dec  3 08:59:25 PM UTC 2024
Tue Dec  3 09:04:55 PM UTC 2024

Sienna_Cichlid /home/roman # df -h
Filesystem                     Size  Used Avail Use% Mounted on
Sienna_Cichlid /home/roman # df -h |grep 03_12
/dev/mapper/backup_03_12_2024  108G   89G   14G  87% /mnt/backup_03_12_2024

--

I just changed the external backup drive to a Crucial P5 Plus 1TB.

Just backup times today - It seems one minute saved because i did not use that dramless junk drive.

Note: more files - as i had temporarily move some photos from another drive to my gentoo linux to preserve it
When i calculated correct 4 minutes 1 seconds (without calculator)

Sienna_Cichlid /home/roman # cat /mnt/backup_05_12_2024/start /mnt/backup_05_12_2024/end
Thu Dec  5 10:59:38 AM UTC 2024
Thu Dec  5 11:03:39 AM UTC 2024

Sienna_Cichlid /home/roman # df -h |grep 05_12
/dev/mapper/backup_05_12_2024   92G   89G     0 100% /mnt/backup_05_12_2024

I'm well aware of that the WD SN570 has worse read and write performance in comparison with a Crucial P5 Plus. I did not expect such a difference.

 

[ShrekOC]

Quote from servethehome:

Perhaps the most important function that DRAM performed in SSDs for generations was as the L2P (logical to physical) table. This is the mapping table functionality that keeps track of where data is physically located on a SSD and gives it a logical mapping so the OS does not need to keep track of the internal SSD data movements.


By moving the L2P tables to main system memory, HMB SSDs are able to get the cost benefits of DRAM-less SSDs while also retaining a lot of performance of SSDs with onboard DRAM.

HMB Functionality is unavailable when using the drive over a USB interface (not sure if Thunderbolt allows NVMe features like HMB). These drives will take a serious performance hit in external enclosures compared to drives with DRAM.

 

[Onasi]

Modern controllers make DRAM-less drives perfectly viable. Pretty much no difference anymore and if you look at W1zz’s reviews they confirm this. Look at individual model’s performance, not just a single spec. Something like the Lexar NM790 is better than most drives on the market, DRAM or not.

 

[Harlow]

Something like the Lexar NM790 is better than most drives on the market

I pulled a brand new Lexar NQ100 240GB 2.5in SATA Windows drive out of an i5-4670K rig and cloned it to an old Samsung 870 EVO 240GB 2.5in SATA. Windows 10 performance which had been sluggish on the Lexar was much improved on the Samsung. Normally I don't notice any difference between DRAMless drives and ones with DRAM, but on this build it made a big difference. I think the more expensive Samsung has DRAM?

 

[freeagent]

I have a few SN770's and they seem pretty decent. But to be fair I have not used them as an OS drive.

 

[Onasi]

@Harlow
Apples to oranges comparison, SATA SSD controllers have essentially stopped evolving and neither of the SSDs you mentioned are “modern”, really (in a functional sense), not to mention that SATA and NVMe are also completely different protocols.

 

[Harlow]

Apples to oranges comparison, SATA SSD controllers have essentially stopped evolving and neither of the SSDs you mentioned are “modern”

True, but the OP did title their request "Are DRAM less drives really such slow junk" and the original data was on a 2006 system. Just because SATA drives are old tech, doesn't invalidate a general discussion about DRAM on SSDs. Perhaps there's a major difference between DRAM implementation on 2.5in SATA SSDs and DRAM on M.2 NVMe drives?

I have one M.2 SATA and a bunch of M.2 NVMe drives in half a dozen tower systems, plus many more SATA drives in older hardware. I still haven't bothered upgrading to NVMe Gen.5, despite this being more commonly available. When buying NVMe, I look at reviews on Tom's for guidance.

 

[ShrekOC]

True, but the OP did title their request "Are DRAM less drives really such slow junk" and the original data was on a 2006 system. Just because SATA drives are old tech, doesn't invalidate a general discussion about DRAM on SSDs. Perhaps there's a major difference between DRAM implementation on 2.5in SATA SSDs and DRAM on M.2 NVMe drives?

I have one M.2 SATA and a bunch of M.2 NVMe drives in half a dozen tower systems, plus many more SATA drives in older hardware. I still haven't bothered upgrading to NVMe Gen.5, despite this being more commonly available. When buying NVMe, I look at reviews on Tom's for guidance.

DRAMless SATA drives present the same problem as NVMe in an USB enclosure: No HMB.