Disk to disk slow transfer rate

[Tolis]

Hi

When using explorer to transfer large files between my ssd disk the transfer rate is maximum 450Mb/s but with MC I only get 15Mb/sec. I use the portable version which I run as administrator on Windows 10.

[Mathias (Author)]

MC is optimized for speed but if some hardware does not support it Windows is using workaround to make it work anyway but the speed suffers..
Also note that the speed Windows Explorer say is often not the "real" speed. But it depends on how large the data is and memory.
Maybe times it is only the speed for the data when it was written to the cache, not the disk.. But it depends.

However all settings that Windows allows to be change for read/write of data can tweaked in settings with Read/Write Settings in Menu > Config > FileOperations Settings > Read/Write Strategy settings
Or just turn it off it Core Settings > FileSystem (tab)
and under the section "Default file operations options" uncheck "Automatically detect read/write stratergy for file copy"
It will then use the settings for the normal read/write profile that is the settings recommended to be the one that work okey for all kind of devices.

(If you tweaking the settings you can see more exact info about the speed (if it is the read or the write that is slow) in the file operations log (Ctrl+L) )

[Tolis]

I unchecked "Automatically detect read/write stratergy for file copy"

and tweak both Normal profiles (same and different disks) however performance not affected at all

did I miss something?

[Tolis]

my files are 10G and you can tell that MC is slow from the time needed to copy

[Mathias (Author)]

It is hard to say you get slow speed, Normally there should not be any reason for that. I got full speed myself when coping between my two ssds.
But reasons for slow down can be so incredible many and so much is affecting the speed.

It can also depends on what settings you tweaked.
For example some drives that have a very large cache, then make sure drive cache is enabled for write.
Also some OS version works better with some buffer size settings then others.

I assume that you start the copy so that MC is doing the copy and not Windows ?
(The MC copy progress dialog is shown and not the one that Windows Explorer shows ? )

In the file operation log you can see if it is the read or if the write that is slow or if it is both.( since each time/speed is logged there separately.)
When you know what part that slows it does then you have a bit more to go on.

[Mathias (Author)]

450 vs 15 is extreme.. And that makes me think that it is some external factors and not just how MC read/writes data.
Normally you get 450 vs 250, and the different is because of real write to the disk and writes that are written to the disk cache