On 11/18/2017 12:56 PM, Robin Laing wrote:
On 18/11/17 03:44, Terry Barnaby wrote:
On 17/11/17 19:35, Luigi Toscano wrote:
Terry Barnaby ha scritto:

For example, I remember some time ago a set of patches in few libraries part
of Frameworks to improve the lookup of the icons, which was hitting the
startup of same applications, and it was not related to QtQuick or QtWidgets.
This is to underline the fact that "tons of small files" may not be the
problem, especially because they can be put together in a resource file.

I didn't say "QtQuick produces the slow startup",  I said "I suspect ..." :)

A statement like "QtQuick produces the slow startup" should indeed be backed up by some evidence,  that would take a bit of work to concisely determine what is happening and would have to be performed by those who know some of the details of the architecture of the KDE5/Plasma system.

It is a fact that KDE5/Plasma is slow to boot/start up on a spinning HDD. There are some figures I and others have posted a while back in this list and lots of people recommend using an SSD when using KDE5/Plasma. As the boot/startup speed difference between a spinning HDD and SSD is so dramatic, this points to lots of small file accesses (seek times are the main culprit of slow HDD access).

I just did some quick and simple tests by using "strace -f -tt -e trace=open,execve -o /tmp/strace_startkde.txt /usr/bin/startkde1" in a shell script place of /usr/bin/startkde (/usr/bin/startkde moved to /usr/bin/startkde1).

With my Fedora25 KDE/Plasma login (Dual monitor and has a manual session setup with Thunderbird, Firefox, Dolphin and 8 konsoles, NFS /home/... ) there are 62122 file opens. (A virgin system default KDE5/Plasma boot/startup still takes a relatively long time). This does include shared libraries /dev, /sys accesses etc. and so a lot of these can perhaps not be really considered as a real file access.

Ignoring /lib64/*, /dev/*, /sys/* and /run/* accesses there are 17276 file opens. The boot/start up takes 52 seconds on a i5-3450 CPU @ 3.10GHz system with a fast SSD with the strace running.

As far as QtQuick, assuming these are the just "*.qm"  and "*.qml" files only there are 1194 file accesses so maybe it isn't the QtQuick side that is the main issue but we would have to time each file read access to really see where the time is being used.

This needs more work, but 62122 file opens just to login to a KDE5/Plasma session seems a bit high !


I for one won't be getting an SSD for me for some time until the price drops to a reasonable range and disk size so that isn't an option.

I do like what you wrote about the strace.  It would be interesting to see what is being done to slow the login process.

I find the boot to sddm is slow enough but isn't done that often so I don't find it as an issue.  The time it takes to login is the big issue.

I would like to try this on F26 and maybe F27 to see if there are many differences.

The list of 62122 file opens is a major issue for just a login.  There is really something that needs to be looked at.

If the KDE development keeps in this direction, it wont' be winning many fans.  I know of one person that has moved away due to the resources being used on their laptop.


Well, Robin, I'll tell you what. I did kick over the traces and bought a 1-TB SSD for SATA buses. I shudder to think of the price I paid. But I was desperate to avoid having to shut down and restart (or may I simply log out and log back in) four or five times a day.

And I have another problem. When I run my system too long, the HDD starts to buzz. In fact, I hear the buzzing sometimes when I start up. Surely that's a sign of the HDD's age, and that if I go on long enough, it will fail.

So here's my plan. When my HP SmartBuy 1TB SSD arrives, and someone comes in to move my data and partitions and so on to it, then put it in, I'll be back here with a review.


PS: has the time come to make those disks insertable, as I once saw done when I took the Microsoft System Engineering class in Windows NT?