Dis (disk usage) graph appears flat with root-on-ZFS on Linux

[grahamperrin]

Kubuntu 25.04 (I used Ubuntu to install with root-on-OpenZFS):

Is this an enhancement request, or (sorry) am I missing something?

I have a limited understanding of https://github.com/htop-dev/htop#runtime-optional-dependencies … do I need CONFIG_TASK_IO_ACCOUNTING=Y for I/O counters?

Thanks

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If it's relevant: after switching to Linux from FreeBSD 15.0-CURRENT (with htop built from source), I reused the htop configuration file from FreeBSD.

[Explorer09]

Your screenshot presents a graph view of the "DiskIO" meter. That's makes me unable to tell what problem you are facing. It is better to show a Text view (style) of the meter for more information.

[grahamperrin]

It seems that bar, text, and LED views do work, whilst forcing some I/O (using Dolphin to seek content 'blah' in home directory):

– however after switching to graph view and waiting (whilst there's similar I/O), there's a flatline.

Version 3.4.0.

[Explorer09]

That's probably not a bug. It can happen when there are many disks in your system. The bar and graph will draw the time when your disks are busy and the bar is full only when all disks are 100% busy at the same time.

[grahamperrin]

Should the bar indicate nothing throughout a fairly long period of significant activity?

Note the percentages (above fifty) in all three shots above; and compare with the disk graph of grkellm in the shot below.

[Explorer09]

Related: #1374
@grahamperrin Currently the bar in the Disk IO meter shows the percentage of time when the disks are busy. It's a different measurement from the I/O rate (KiB/s, MiB/s or like). While I don't have GKerllM to verify myself, it seems that its disk monitor plots the graph about I/O rates. I have a plan for a PR to implement the DiskIORate as a separate meter from DiskIOTime, so that user can have both graphs plotted. 🙂 Just wait a bit until I make a draft of it.

[Explorer09]

Update: The draft is in #1763.