DK Performance: thumbnails and browsing feels extremely sluggish - am I doing anything wrong?

[Gilles Caulier]

You don't needs debug symbols version. Debug traces are only prints on
the console. Check if you have enabled the internal debug logging
option from digiKam Setup/Miscs/System dialog page:

https://docs.digikam.org/en/setup_application/miscs_settings.html#system-settings

Default settings from DebugView is enough.

Best

Gilles Caulier

Le mar. 9 mai 2023 à 09:25, Thomas <sdktda at gmail.com> a écrit :
>
> I tried running dbgview as Administrator and enabling various other
> capture options such as kernel capture, global capture etc. However, it
> did not seem to make a difference.
>
> Do I need a special version of DK with debug symbols compiled in or
> something like that?
>
>
> On 2023-05-08 18:48, Maik Qualmann wrote:
> > Create a DebugView log (download from Microsoft). Activate in the digiKam
> > settings under System-> internal debugging, start digiKam again. Start
> > DebugView before, do things in digiKam that are slow and post the contents of
> > the DebugView window.
> >
> > Maik
> >
> > Am Montag, 8. Mai 2023, 16:01:34 CEST schrieb Thomas:
> >> Hi,
> >>
> >>
> >> First some background:
> >>
> >> I have a fairly big collection.
> >>
> >> Currently at more than 700 GB and more than 400k images.
> >>
> >> Collection is hosted on a NAS over 1 GbE LAN.
> >>
> >> The NAS server is plenty fast Xeon machine with 4 disks in RAID-1. The
> >> files are shared via a samba server on Debian.
> >>
> >> I have various client machines but they all express similar behavior.
> >> The one I use the most is a fairly recent Windows machine with  i7 CPU
> >> and 64 GB RAM and NVMe disk.
> >>
> >> My collection databases and sizes are shown below. Database files are
> >> hosted locally on the NVMe.
> >>
> >>
> >> The behavior I experience:
> >>
> >> When I click a person in "People" tab, it is often many seconds or even
> >> minutes before it shows the actual thumbnails of faces for this person.
> >>
> >> I just tested this right now by clicking a random person in the list.
> >> There were only 9 images of this person and it took more than 15 seconds
> >> before the thumbnails were shown.
> >>
> >> I took another person and did the same. This person had more than 8k
> >> images. They were shown immediately in the top. But scrolled a but down,
> >> the thumbs were blank. So I did that and waited. It took several minutes
> >> (more than 2) for the thumbs to be shown this far down (probably about
> >> 10 % scroll down). I then scrolled a bit further down and they were
> >> blank also. Took several minutes for DK to show thumbs.
> >>
> >>
> >> Are these thumbnails not cached in the thumbnail database?
> >>
> >> I mean, all the DK database files are less than 6 GB. They can easily
> >> fit in RAM. Even if they had to be read from the NVMe, the entire 6 GB
> >> can be read from NVMe disk in less than 7 seconds. (tested it using raw
> >> read of the files without them being cached).
> >>
> >>
> >> Another issue happens when I go to Albums and find some image. Then
> >> doubleclick it to open the image in preview mode. It often takes several
> >> seconds to open the image. Now, I am not sure if the preview is actually
> >> loaded from the NAS or if it is loaded via the thumbnaildb? But it not
> >> unusual for this to take 5 seconds or more. This makes browsing images
> >> feel extremely sluggish.
> >>
> >>
> >> So what is happening here? Is it something wrong in my setup?
> >>
> >>
> >> What is the most likely bottleneck here?
> >>
> >>   1. The database files? If so, are they properly indexed? Are the proper
> >>      settings used relating to sync, locking, etc? Are the databases
> >>      loaded into memory or cached in memory when there is sufficient RAM?
> >>   2. Is the NAS to blame? I monitor performence metrics relating to disk
> >>      and I/O on the machine and I see no obvious bottlenecks / high
> >>      utilization on the server while doing the above actions with DK.
> >>   3. Is the samba network protocol to blame?
> >>   4. Hardware on client or server (I have a hard time seeing this being
> >>      the case)
> >>   5. Is it the network bandwidth between NAS and clients? This is low
> >>      latency 1 GbE ethernet. It can easily do about 100 MB/s and I have
> >>      verified this using iperf.
> >>
> >> Could it be something else entirely?
> >>
> >>
> >> I would love to hear other users' experiences with how DK performs as
> >> well as your collection/db sizes as well as client and server specs.
> >
> >
> >
> --
> Mvh
> Thomas
>