(SOLVED) T for Win -600MBs then 100MBs

[kris455]

edit: Jump to end. Support had me try booting to Image for Linux. WOW!!!

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I use either win10 current or usb boot stick.
Backing up about 120GB in use on a 500 GB ssd nvme Sam 970. Mixed win and Mint.

To either a WD BL 1T nvme
or a brandy new Sam 990 1T evo nvme.

Connected to Lenovo P15s Laptop USB C port. if I try slower C port it still clamps after a short bit.
SSK enclosure rated 10Gb and crystal benches it at ~1024MBs

backups start out at 6 or 700MBs and then after a variable time drop to ~130MBs for the rest of the now very tedious backup. Turns a 6 min backup into an 11 min backup.

Wondering why.

Not a recent problem but getting very frustrated with it.
ver 3.61a

[TeraByte Support]

probably because windows cache (fast) is full and now you only have the bandwidth available via USB and the Drive. If using USB3, ensure you use USB3 cable with a USB3 device, make sure it's a higher quality type cable.

But it can also be if there is small sized consecutive blocks with high fragmentation on the source or target.

[OldNavyGuy]

Also cross-posted on Ask Woody forum...

https://www.askwoody.com/forums/topic/b ... st-2654901

[OldNavyGuy]

NVMe drives tend to run hot.

They have a feature called "thermal throttling" that will slow down the drive to prevent overheating.

Check with the drive manufacturer for the max operating temp. They may also have an app that will give you temp warnings and notifications when the drive is throttling.

WD recommends not higher than 72C.

Good airflow in the case would be helpful.

[TeraByte Support]

speaking of heat, a CPU running hot can slow things down for same reason of throttling.

[kris455]

It's not heat. I installed a different backup software and it backed it up in about 12 min which averages about 200MBs. And the chip was red hot. No change in speed throughout - ~1.2Gbs was what it said.

Not windows cache since same prob happens when I run it standalone boot to USB stick.

USB cable is 3.2 and rated 20GBs. I bought it specially and it is the best of all the other cables I have.

The clamp happens at a different time each test run. Is there a way to clamp the transmission speed?

[kris455]

Terabyte running in windows: Just did 115GB in 5:57 min to an old Sammy 870 EVO sata / Unitek / USB3.? Only one dip that lasted maybe 10 seconds. The nvme used to work fine. Now not. Even the new one. Slower than the old sata as external.

[TeraByte Support]

There is still a cache involved and fragmentation. It's basically just going as fast as it can (though windows) and if a drive can't keep up, it just slows down until it can. Of course issues like bad/questionable sectors would have an effect.etc..)

If you wanted to throttle output for some reason there is the various /tmbps, /tsecs, /tintv options available.

[Fracso]

I created a 27 GiB image in a SSK (SHE-C325 PRO) enclosure (256 NVMe installed), using IFW 3.64 from a UFD. USB 10G link, connection to a USB-C port in a Lenovo ThinkPad 495s, charger connected.

Results: no abrupt changes in speed, peaks about 440MB/s, average 238 MB/s (rather slow). In validation, average was 503 MB/s.

I also tried with IFL 3.64 (Secure Boot disabled, otherwise doesn´t work). Averages were higher, as expected: creation 280 MB/s, validation 697 MB/s.

[Brian K]

Check your drives for fragmentation. I get 1200 MBps when there is no fragmentation. NVMe to NVMe.