SUMMARY File transfer speeds using Dolphin are significantly slower than using other file managers. On my system disk to disk transfer speeds are around 40 MiB/s and LAN transfer speeds are around 20 MiB/s. Using Konqueror these speeds double while using Nautilus I am achieving expected results of around 100 MiB/s. STEPS TO REPRODUCE Just transfer any file to anywhere. This has been reported by multiple users on the Kubuntu forums recently: https://www.kubuntuforums.net/showthread.php/74798-Realtek-driver-r8169-slow-network-speed OBSERVED RESULT LAN transfer speed of around 20 MiB/s. EXPECTED RESULT Transfer speed of around 100 MiB/s. SOFTWARE VERSIONS KDE Plasma Version: 5.12.7 KDE Frameworks Version: 5.447.0 Qt Version: 5.9.5 ADDITIONAL INFORMATION
midnight commander, mc, also shows the speed. Dolphin was not exceedingly fast here either.
Not really anything to do with Dolphin but KIO. I'm curious why Konqueror is purportedly quicker. Can you be more specific what kind of "LAN" transfer you're talking about? We did some significant (like 20x improvement) fixes to the SFTP slave recently, not sure if that was released in Applications 18.12, though, it might have missed the merge window.
OK first off the slow speed is apparent in disk to disk transfers when both disks are connected to the same controller, the reported speed is 40 MiB/s. This is less than half the speed reached by Nautilus or Windows File Manager on the same hardware. My LAN is a Kubuntu 18.04 > Archer C7 Router > Ubuntu 17.10. The connection is via CAT 6 cable and each run is less than 15m. The tests I did involved a 3 GB movie file moved from a directory on the Kubuntu PC to the Home directory on the Ubuntu PC and then moved back to a folder in the a disk not containing the Kubuntu Home directory (ie a 2nd HDD). Both of these PCs have multiple HDDs so these tests were just transferring the same 3 GB file from one disk on the PC to another disk on the same PC. Please note these tests were back to back on the same hardware, run sequentially within 40 minutes, transferring the same file. In my ignorance I will state that it does not seem to be a SFTP problem on 2 grounds, 1/ Nautilus hits LAN transfers of around 100 MiB/s which is close to the expected top speed for a sustained domestic LAN transfer and 2/ I don't believe SFTP is used in a transfer from one HDD in a PC to another HDD in the same PC. I regularly deal in file transfers where the file sizes range between 20 GB to 70 GB and the speed difference is very noticeable, ie 5 to 10 minutes longer per file transfer. At the moment I consider Dolphin unfit for purpose and unusable.
Tested here with Dolphin 18.12.3 and nautilus 3.32. I copied a 8.2 GiB file from an hard disk formated with ntfs file system to another hard disk formatted with ext4. Dolphin speed varied between 140 and 160 MiB/s according to notifications applet. Nautilus speed varied between 155 and 160 MiB/s also according to notifications applet. Operating System: Arch Linux KDE Plasma Version: 5.15.4 KDE Frameworks Version: 5.57.0 Qt Version: 5.12.2 Kernel Version: 5.0.7-arch1-1-ARCH
Repeated the tests with Kubuntu 19.10 and the transfer speed seems to have approximately doubled to around 40 Mib/s.
Git commit 10cf5aca5b3da2608eaf2967415d0b09b36121ac by Méven Car. Committed on 04/04/2020 at 18:52. Pushed by meven into branch 'master'. File ioslave : use Better setting for sendfile syscall Summary: Changes : * use sendfile when copying file bigger than 2 GB * copy 512 kB instead of previously 32 kB for each sendfile or read/write copying iteration This effectively increase the copying speed, since the filesystem is asked to copy more at once, it lets it reach higher speed before getting the next data to copy. Related: bug 342056 Test Plan: Copying large files or folders with medium sized files (for instance photos) is noticebly faster. Reviewers: #frameworks, dfaure Reviewed By: dfaure Subscribers: bruns, broulik, kde-frameworks-devel Tags: #frameworks Maniphest Tasks: T11627 Differential Revision: https://phabricator.kde.org/D28555 M +3 -5 src/ioslaves/file/file_unix.cpp https://commits.kde.org/kio/10cf5aca5b3da2608eaf2967415d0b09b36121ac
Is this still an issue with KIO >= 5.69.0 ?
I am getting around the 60-70 MBps range. not fantastic but a huge improvement over the speed when the ticked was raised.