Car: Dolphin 26.08 and KIO performance improvements [LWN.net]

Méven Car has written a pair of interesting blog posts (part 1, part 2). The first post is largely about some of the recent new features and performance work that have gone into the Dolphin file manager 26.08 release, as well as the KIO framework. The second looks at the performance improvements and benchmarks for previous, current, and upcoming releases.

Copying many small files is more than twice as fast as it was in April. The gain falls off as files get larger, which is what you would expect: the fix is to the per-file overhead, and once each file carries a megabyte of actual I/O the overhead stops being what you are waiting for.

There is still a gap with cp, discussed at length in the July post. KIO is doing more than cp does, but not five times more, and the batching work that closes most of the rest of that gap is still in progress.

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Kool

Posted Aug 29, 2026 1:14 UTC (Sat) by gerdesj (subscriber, #5446) [Link] (2 responses)

I love KDE and have used it for quite some time and I will insist on calling the whole thing KDE. I think my first introduction was a self compiled effort of 1.2? on a Slackware job in the late '90s.

Now if Dolphin could stop getting its knickers in a twist over whether a file system is available or not, that would be nice and modern.

For example, I use pam_mount to mount a few Windows shares on login. A desktop is pretty stable and this is fine. A laptop that wanders around and has a VPN that comes and goes etc is a different beast. Dolphin freezes when mounts are unavailable.

I'm hoping to use SMB over QUIC and a Kerb proxy to make Windows shares more immediately available but it would be nice if Dolphin treated mounts with a modern approach. Times have changed.

Kool

Posted Aug 29, 2026 8:22 UTC (Sat) by barryascott (subscriber, #80640) [Link] (1 responses)

Is this reported to kde in their bug tracker?

Isn’t the issue that the smb mount seems alive until a timeout happens?

Kool

Posted Aug 31, 2026 1:57 UTC (Mon) by mathstuf (subscriber, #69389) [Link]

I've had an issue Linux-wide (not Dolphin-specific) that network namespace-specific smb mounts hang when accessed from processes not in the "correct" network namespace. Makes sense; not sure if the kernel could detect that an smb mount is using something netns-specific to fail faster with a more useful error message or not.

Not reported anywhere else because it's been easy to avoid the problem (not using graphical file browsers that can see the mount point but go berserk when they can't gather information about it).

Memory usage torture tests

Posted Aug 29, 2026 1:59 UTC (Sat) by collinfunk (subscriber, #169873) [Link]

Cool benchmarks. I'm curious if they experimented with more extreme memory usage tests.

It predates my involvement in GNU coreutils, but in 2014 someone did this with 'cp' out of their own curiosity and it was a memorable read [1]. I sort of admire their patience leaving it running for ~10 days. Also a good reminder that free'ing memory isn't free, if you consider time valuable.

[1] https://lists.gnu.org/archive/html/coreutils/2014-08/msg0...