User profile for user: wessongroup
wessongroup Author
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Slow USB-C transfer rates

Only getting 197 Mb/s transfer rate using USB-C ... Mac mini to external 2-10TB Seagate HDD in a Mediasonic HF2-SU31C 4 bay (2 10TB)


System report does not show Thunderbolt connected .... No devices listed as connected


The four bay Mediasonic has one USB-C port and came with a USB-C cable to connect to the USB-C port on the computer


Transfer 5.7 TB last night ... Took 9 hours and 37 minutes


Going a little faster between the Seagate drives this morning ... 197.27 Mb/s ... the first transfer was only 147,2

Mac mini, macOS 10.14

Posted on Apr 7, 2019 9:17 AM

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User profile for user: HWTech
HWTech
User level: Level 9
68,726 points

Posted on Apr 11, 2019 6:53 AM 

The SATA drive has a stated transfer speed of 6Gb/s using USB 3.1 ... I 
would hope to see speed a bit higher than what I saw in the 6TB transfer
 between two 7200 rpm drives using a USB-C connection.

You've just encountered marketing speak which tricks people into believing things which are impossible. I see this all the time in the promotional materials for products. The SATA III interface has a maximum transfer rate of 6Gb/s as you state, but hard drives can only transfer data at 60-150MB/s typically. An SSD is the only consumer drive which can maximize the transfer rate of the SATA III bus. If you look at the product page for your Seagate drive, it will state a maximum transfer rate of 220MB/s which is really high for a hard drive.


You have to read the marketing materials very carefully to parse out whether the stated speeds are actual real world numbers you can expect when using the device or whether those numbers are just describing the maximum capabilities of the various chipsets of the controllers (SATA III, USB3.x, etc.). I hate buying things these days because of the misleading advertising information because it takes me so long to figure out the actual capabilities of various devices.


Example: When trying to buy a USB3.1 Gen1 hub you will find almost every hub stating they are USB 3.1 Gen1 compatible which is technically correct. It will mention USB3.1 Gen1 with speeds up to 5Gb/s which is the maximum transfer rate of the USB 3.1 Gen1 spec. but not necessarily the hub if the hub uses only a USB2 chipset. They trick people by describing the specification of USB 3.1 Gen1 instead of the actual specifications & capabilities of their own device (a hub in this case). If the hub is using a USB2 chipset, then you will not see very fast speeds, but it will work very slowly when connected to a USB3.1 Gen1 laptop (hence the "compatibility").


Also, USB-C is a only a connector type. I wish they would never have named it after USB as it confuses everyone including techs. The transfer rate is based on the protocol being used by the controller whether it is USB3.1 Gen1 or USB3.1 Gen2 or USB2 or Thunderbolt 2, etc.

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User profile for user: HWTech
HWTech
User level: Level 9
68,726 points

Apr 11, 2019 6:53 AM in response to wessongroup 

The SATA drive has a stated transfer speed of 6Gb/s using USB 3.1 ... I 
would hope to see speed a bit higher than what I saw in the 6TB transfer
 between two 7200 rpm drives using a USB-C connection.

You've just encountered marketing speak which tricks people into believing things which are impossible. I see this all the time in the promotional materials for products. The SATA III interface has a maximum transfer rate of 6Gb/s as you state, but hard drives can only transfer data at 60-150MB/s typically. An SSD is the only consumer drive which can maximize the transfer rate of the SATA III bus. If you look at the product page for your Seagate drive, it will state a maximum transfer rate of 220MB/s which is really high for a hard drive.


You have to read the marketing materials very carefully to parse out whether the stated speeds are actual real world numbers you can expect when using the device or whether those numbers are just describing the maximum capabilities of the various chipsets of the controllers (SATA III, USB3.x, etc.). I hate buying things these days because of the misleading advertising information because it takes me so long to figure out the actual capabilities of various devices.


Example: When trying to buy a USB3.1 Gen1 hub you will find almost every hub stating they are USB 3.1 Gen1 compatible which is technically correct. It will mention USB3.1 Gen1 with speeds up to 5Gb/s which is the maximum transfer rate of the USB 3.1 Gen1 spec. but not necessarily the hub if the hub uses only a USB2 chipset. They trick people by describing the specification of USB 3.1 Gen1 instead of the actual specifications & capabilities of their own device (a hub in this case). If the hub is using a USB2 chipset, then you will not see very fast speeds, but it will work very slowly when connected to a USB3.1 Gen1 laptop (hence the "compatibility").


Also, USB-C is a only a connector type. I wish they would never have named it after USB as it confuses everyone including techs. The transfer rate is based on the protocol being used by the controller whether it is USB3.1 Gen1 or USB3.1 Gen2 or USB2 or Thunderbolt 2, etc.

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User profile for user: wessongroup
wessongroup Author
User level: Level 1
9 points

Apr 8, 2019 9:45 AM in response to wessongroup

This is the model of HDD I’m using in your device Medisonic


Seagate BarraCuda Pro Performance Internal Hard Drive SATA HDD 10TB 6GB/s 256MB Cache 3.5-Inch (ST10000DM0004)


This is what is being reported under my system report as to the 3.1 connection


Both HDD drives are showing up as operating under the 3.1 USB interface



USB3.1 Hub

       

  Product ID: 0x8820

  Vendor ID: 0x2109  (VIA Labs, Inc.)

  Version: c.13

  Speed: Up to 10 Gb/sec

  Manufacturer: VIA Labs, Inc.     

  Location ID: 0x01200000 / 1

  Current Available (mA): 500

  Current Required (mA): 0

  Extra Operating Current (mA): 0


USB3.1 SATA Bridge:


  Product ID: 0x0715

  Vendor ID: 0x2109  (VIA Labs, Inc.)

  Version: 1.36

  Serial Number: 0000000000000004

  Speed: Up to 10 Gb/sec

  Manufacturer: VIA Labs,Inc.

  Location ID: 0x01240000 / 3

  Current Available (mA): 500

  Current Required (mA): 8

  Extra Operating Current (mA): 0


USB3.1 SATA Bridge:


  Product ID: 0x0715

  Vendor ID: 0x2109  (VIA Labs, Inc.)

  Version: 1.36

  Serial Number: 0000000000000003

  Speed: Up to 10 Gb/sec

  Manufacturer: VIA Labs,Inc.

  Location ID: 0x01230000 / 4

  Current Available (mA): 500

  Current Required (mA): 8

  Extra Operating Current (mA): 0


USB3.1 SATA Bridge:


  Product ID: 0x0715

  Vendor ID: 0x2109  (VIA Labs, Inc.)

  Version: 1.36

  Serial Number: 0000000000000002

  Speed: Up to 10 Gb/sec

  Manufacturer: VIA Labs,Inc.

  Location ID: 0x01220000 / 2

  Current Available (mA): 500

  Current Required (mA): 8

  Extra Operating Current (mA): 0

  Media:

M0004-1ZC101:

  Capacity: 10 TB (10,000,831,348,736 bytes)

  Removable Media: No

  BSD Name: disk5

  Logical Unit: 0

  Partition Map Type: GPT (GUID Partition Table)

  USB Interface: 0

  Volumes:

EFI:

  Capacity: 209.7 MB (209,715,200 bytes)

  File System: MS-DOS FAT32

  BSD Name: disk5s1

  Content: EFI

  Volume UUID: 0E239BC6-F960-3107-89CF-1C97F78BB46B

Movies:

  Capacity: 10 TB (10,000,487,374,848 bytes)

  Available: 5.32 TB (5,315,246,817,280 bytes)

  Writable: Yes


Long story short ... very disappointed at the slow transfer rate using USB 3.1

  File System: Journaled HFS+

  BSD Name: disk5s2

  Mount Point: /Volumes/Movies

  Content: Apple_HFS

  Volume UUID: 2376369F-4CF6-3380-8D9B-6E3C631420A7


USB3.1 SATA Bridge:


  Product ID: 0x0715

  Vendor ID: 0x2109  (VIA Labs, Inc.)

  Version: 1.36

  Serial Number: 0000000000000001

  Speed: Up to 10 Gb/sec

  Manufacturer: VIA Labs,Inc.

  Location ID: 0x01210000 / 5

  Current Available (mA): 500

  Current Required (mA): 8

  Extra Operating Current (mA): 0

  Media:

M0004-1ZC101:

  Capacity: 10 TB (10,000,831,348,736 bytes)

  Removable Media: No

  BSD Name: disk2

  Logical Unit: 0

  Partition Map Type: GPT (GUID Partition Table)

  USB Interface: 0

  Volumes:

EFI:

  Capacity: 209.7 MB (209,715,200 bytes)

  File System: MS-DOS FAT32

  BSD Name: disk2s1

  Content: EFI

  Volume UUID: 0E239BC6-F960-3107-89CF-1C97F78BB46B

New Movies:

  Capacity: 10 TB (10,000,487,374,848 bytes)

  Available: 5.4 TB (5,395,128,057,856 bytes)

  Writable: Yes

  File System: Journaled HFS+

  BSD Name: disk2s2

  Mount Point: /Volumes/New Movies

  Content: Apple_HFS

  Volume UUID: 118DD548-548C-3F6E-AC8B-A5DD091E5ED6


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User profile for user: HWTech
HWTech
User level: Level 9
68,726 points

Apr 10, 2019 8:03 PM in response to wessongroup

I cannot load the product page at the moment, but I don't believe this box supports RAID so you are getting normal hard drive speeds which should be expected. If you installed SSDs, then you should see somewhere around 400-500MB/s. Just because the interface supports 10Gb/s doesn't mean it can make standard SATA hard drives perform beyond their abilities. If you want faster speeds with traditional desktop hard drives, then you need to use RAID.



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User profile for user: wessongroup
wessongroup Author
User level: Level 1
9 points

Apr 11, 2019 5:37 AM in response to HWTech

The SATA drive has a stated transfer speed of 6Gb/s using USB 3.1 ... I would hope to see speed a bit higher than what I saw in the 6TB transfer between two 7200 rpm drives using a USB-C connection.


I understand these transfer rates are theoretical .... However, the speeds I'm seeing are NOT close to stated transfer rates of USB 3.1 we all see promoted


"An SSD speed comparison will reveal that there is a wide variation between SSDspeeds. But to get an idea of the performance difference an SSD v HDD speedcomparison could reasonably show, a standard SSD can read sequential data at a speed of about 550 megabytes per second (MBps) and write it at 520 MBps."


You are correct the "box" does not support RAID ... That was my choice based on my understanding of RAID0 and its data sharing structure


I would have been happy with 5Gb/s ... However, I was unable to achieve this transfer rate under load


Thanks for the response





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Slow USB-C transfer rates

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