Bug 357465

Summary: nfs async write causes CPU to spike 100%, plasma to freeze, incorrect write speed. Sync works however
Product: [Frameworks and Libraries] frameworks-kio Reporter: doug <dougiemaca>
Component: generalAssignee: Unassigned bugs <unassigned-bugs-null>
Status: REPORTED ---    
Severity: normal CC: jjm, joseph, kdelibs-bugs-null
Priority: NOR Keywords: efficiency-and-performance
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description doug 2016-01-03 10:53:05 UTC 
Using a laptop with wireless connection to router
KDE Plasma Version: 5.5.2
QT Version 5.5.1
Kernel Version: 4.4.0-1-MANJARO
nfs-utils 1.3.3-3
fstab entry: 192.168.1.67:/volume1/share               /home/doug/NAS nfs     vers=4,noauto,user,noatime,x-systemd.device-timeout=10,timeo=14,intr,soft 0 0

Hi there,

When copying large files to an nfs4 drive mounted as async the copying notification plasmoid freezes, cpu maxes out, dolphin freezes, write speed in the copying notification is incorrect and then disappears.

This can be worked around by mounting as sync in fstab but this has slower read / writes. Can the async behaviour be fixed? In other desktop environments mounting as the default option async is not an issue.

*strangely if it is mounted as async copying files over from the nfs drive to laptop does not seem to be a problem. Even the copy speed within the copying notification is correct.

Reproducible: Always

Steps to Reproduce:
1. mount nfs4 drive as async on wireless laptop connection
2. copy large file to nfs drive 
3.
Comment 1 Jonathan Marten 2021-02-05 14:33:02 UTC 
Accessing NFS mounted folders is handled in the same way as local file access as far as KIO is concerned; that is, by the 'file' ioslave.  The NFS ioslave in kio-extras provides access to remote NFS servers (without the need for mounting) via URLs starting "nfs://host/".  Reassigning to frameworks-kio/general.