[konsole] [Bug 405798] New: Konsole becomes unusable after a search is made, even after cancellation

[A. Wilcox]

https://bugs.kde.org/show_bug.cgi?id=405798

            Bug ID: 405798
           Summary: Konsole becomes unusable after a search is made, even
                    after cancellation
           Product: konsole
           Version: 18.12.2
          Platform: Compiled Sources
                OS: Linux
            Status: REPORTED
          Severity: major
          Priority: NOR
         Component: history
          Assignee: konsole-devel at kde.org
          Reporter: awilfox at adelielinux.org
  Target Milestone: ---

SUMMARY
Let us assume we have a large scrollback buffer in a Konsole tab, from
compiling a lot of packages.  (I am a distro package maintainer.)

Let us also assume I need to search the scrollback for a phrase.  So I use
Konsole's search functionality.  I type in a phrase ("libjni" in this case). 
It scrolls to the result after a considerable amount of time, highlighting it
in red.  The entire Konsole process is very laggy and unresponsive (even in
other tabs) during this time; even switching tabs takes multiple seconds.

Even after closing the search view, Konsole continues to be laggy for at least
10 minutes until it finally finishes.  All the while, the terminal tab shows
"activity" (possibly highlighting other matches? not sure) even though there is
no activity happening in that terminal tab.


STEPS TO REPRODUCE
1. Build software in a Konsole tab.  Lots of scrollback; my example had 173 MB
of history.
2. Attempt a search in the tab.
3. Close / cancel the search.


OBSERVED RESULT
Still extremely laggy for minutes.


EXPECTED RESULT
No more lag after the search is closed or cancelled, even if the rest of
history has not been searched yet.


SOFTWARE/OS VERSIONS
Linux gwyn 4.14.88-mc13-easy-power8 #1 SMP Fri Feb 22 21:12:46 UTC 2019 ppc64
KDE Plasma Version: 5.12.7
KDE Frameworks Version: 5.54.0
Qt Version: 5.9.7


ADDITIONAL INFORMATION

-- 
You are receiving this mail because:
You are the assignee for the bug.