GL-AR750 super slow Write/Read Speed on SD-Card

Hi Folks,
hope to get some help on this topic:
I put in a high speed 64GB SD-Card (Using the card in a Notebook gives me ~20MB/sec) and even tried another one…
But when i try to copy or read some files this is what i get on my GL-AR750:
Writing on in: 0,9MB/sec max
Reading: 1,7MB/sec max.

NTFS or ext4, does not make a difference.
exFat is not available anymore unfortunately.

I had fairly good experience with an old exFat USB-Stick a year ago where i could get up to 5MB/sec which was satisfying for me but i need the USB Port for another device now thus the SD-Card for a smb storage.

Any ideas what the bottleneck might be or happened with the 3.xxxx Firmwares ??
The mount.ntfs-3g process goes up to 44% Cpu load when writing if that helps…
I would be satisfied if i could get at least 5MB/sec again…

Journaling is probably affecting the speed here. Try formatting the card with EXT4 without Journaling.

Like this:

I also tried ext2 which does not have journaling, but also no differences :frowning:


Do you have more cards to test? I saw some users in the forum long ago posted that some cards were slow but not others. I guess it depends on the control chip.

Yes, i tried another one, no difference.
Both Cards are significantly faster in a Computer or even a digital Camera (recording a movie).

Thus the reason must somehow be the Router.
Today just out of curiosity i even tried a USB Stick which also was awful slow.

Of course i also did a factory reset, hoping it might be a messed up configuration…

What is the speed you are getting ?

I use the fat32 USB stick and it can get 4-5MB. NTFS is for sure slowed down due to ntfs-3g.
But I’m not satisfied with 4-5MB, it should be able to 300Mb which is 30MB, right?

The bottleneck is the IO speed of the SoC. 4-5MB is normal.

When I observe the CPU usage, it only about 30% while transferring the data.
I see the memory is DDR1 of low frequency. So that may be due to the old memory?