SSD Drives

[TrevorW]

Recently purchased a Samsung 2TB SSD drive over another HDD drive for data retention of my image files which currently are residing on a external HDD. I purchased the SSD drive over another HDD on the fact the packaging said up to 460- mbs transfer rate - well suffice it to say the transfer rate has not exceeded 40 mbs between the two devices - I should have known better than to believe the packaging as this transfer rate.


My PC has a SSD internal drive and even transferring files between the two the speed initially started out at over 100 mbs then quickly dropped off to 38 mbs

[joshman]

how are you connecting the SSD to your computer? what model of Samsung SSD?

EDIT, just re-read you post, are transferring from a spinning platter HDD to an SSD? Chances are the connection of your external spinning HDD is the bottleneck here.


I've got several SSD's, both internal and external, and regularly see transfer speeds upwards of 800MB/s (megabytes!)

[TrevorW]

I have an internal SSD which is the boot drive and even transferring to the new External SSd via USB 2 port transfer speed only 38 mbs :)

[joshman]

yup...that's about the practical limit of USB2...


FWIW, the 460mbs on the packaging is most likely 460megabit/s = 57.5megabytes. and that is the maximum theoretical throughput.


That's about as good as you're going to get in that configuration.


What Samsung SSD did you get?

[TrevorW]

Samsung T5 EVO 2tb $199 from office works - I found I have usb 3 port on MB and thats started out at 300mbs transfer rate then quickly dropped to 38 mbs :)

[Dave882]

I’m not sure about the bigger drives, but I have found most flash drives equally disappointing. The advertised speed is far from the actual transfer rates.

However, I recently purchased one of these usb 3.2 drives:

https://www.officeworks.com.au/shop/officeworks/p/sandisk-128gb-extreme-pro-usb-3-2-solid-state-flash-drive-sdcz880128

They are excellent! Truely exceptional speed and I can confidently do planetary high speed captures direct to the external drive too. Expensive, but office works will price match the Amazon prices…

Perhaps you can find a similar usb 3.2 device in a larger format but I’d say it’d be very very pricey.

[Leo.G]

Dave is that USB-C or standard USB-A 3.2?



Aren't you using a fancy, expensive camera Dave, I mean a higher end ZWO or something?
I have a little Player One Neptune and would love to be able to go straight to external storage media.
Then again I'd love an old laptop with USB-3. I currently use my sons HP I purchased new for him in 2011, it's an i5 processor but the USB-3 is via a PCMCIA plug in card that keeps popping out and not much fun.



Data transfer and speeds are always an issue and I NEVER believe manufacturers specifications. They are much like fuel efficiency figures as stated by VW and most auto manufactures, yes, push the vehicle out of an aeiroplane at 30.000 feet with the engine idling and you'll come close to manufacturers claims, otherwise, total hogwash.
In saying that vehicle manufacturers are being held to some standards and getting closer, drive manufacturers however.....


Throw in kibibits and mebibits and all of the other crap to metricise drives.......
We loose, I remember when my 2TB hard drives came with a 2TB capacity.
1024GB=1TB
Throw metric into the equation (strange, even the Americans are doing it and they HATE metric) 1000GB=1TB. Manufacturers love it, they sell you lesser capacity at the higher price.



That's the maths I learnt when I first studied computers/programming as part of my engineering course (electronics) back in the mid to late 80s.

[Dave882]

Leo- for planetary I use asi462mc and asi178mm… not too super faancy lol but you need to transfer lots of data veeery quickly when you’re shooting at 100-120fps. It’s just a normal usb type an interface but my MacBook has a type-c so I use an adaptor.

[TrevorW]

I am only using the drive as a storage medium - :)

[garymck]

I use a Samsung T7 external ssd and get 900 mb/sec sustained on my MacBook Pro, got the same figures on a a Lenovo gaming laptop....no issues with this at all. Cable or port problem?
Gary

[Leo.G]

I'm thinking of getting a portable SSD to take out for imaging if I can get a used laptop with USB-3 eventually). I would only buy Samsung, no particular reason I'm just somewhat fussy with drives and branding, over the 30+ years I've been building and repairing computers I've learnt there is a difference. Though, I usually don't play with SSD drives but did just put an M2-m in my sons recent computer build because it had a port on the motherboard for one, a 1TB Samsung. For his primary drive I bought a 4TB Ironwolf from Seagate. The Barracuda series doesn't have the best platter use system (SMR vs CMR - Shingle magnetic recording--Conventional magnetic recording, the latter is what's used in server gear for a good reason but costs more) whereas the Ironwolf for the server equipment has the better system. $159 for a 4TB server hard drive new is EXTREMELY cheap.


https://www.howtogeek.com/803276/cmr-vs.-smr-hard-drives-whats-the-difference/


I know, this has nothing to do with SSD drives but many people still use conventional platter drives within their systems.

[bxobservatory]

For our observatory I just bought a five slot NAS comprising five ironwoolf 2tb drives which I will configure as a raid5 system. That’s fronted by a 1tb ssd cache, that should provide us with a reasonable amount of storage with the ssd cache providing the performance I require for uploading 50MB images every 30 seconds (RASA 11, Zwo 2400 camera) on our 1Gb network.