Bug 1021330

Summary: slowdown of some executables startup
Product: [Fedora] Fedora Reporter: Jan Kratochvil <jan.kratochvil>
Component: prelinkAssignee: Jakub Jelinek <jakub>
Status: CLOSED EOL QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 22CC: jakub, mjw
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Target Release: ---   
Hardware: x86_64   
OS: Linux   
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Fixed In Version: Doc Type: Bug Fix
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Clone Of: Environment:
Last Closed: 2016-07-19 10:30:12 UTC Type: Bug
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Jan Kratochvil 2013-10-21 06:20:54 UTC
Description of problem:
Randomly picked mplayer (rpmfusion) and it slows down its startup.
In other cases (./configure run) it really speeds up the startup as expected.

Version-Release number of selected component (if applicable):
prelink-0.5.0-1.fc19.x86_64

How reproducible:
Always.

Steps to Reproduce:
rm *;sync;(time for i in `seq 0 89`;do mplayer &>/dev/null -nosound -vo png -ss $i -endpos 0 video.mp4;mv 00000001.png $i.png;done) 2>&1|grep ^real|tee -a /tmp/times

Actual results:
without prelink:
6.220s 6.212s 6.218s 7.463s 6.277s 6.216s 6.203s 6.255s 6.209s 6.205s

with prelink:
6.560s 6.496s 6.501s 6.530s 6.583s 6.616s 6.511s 6.498s 6.489s 6.915s

Expected results:
with prelink times should be <= without prelink times

Additional info:
-=without prelink
+=with prelink
 runtime linker statistics:
-  total startup time in dynamic loader: 28010379 clock cycles
+  total startup time in dynamic loader: 34141440 clock cycles
-	    time needed for relocation: 19069899 clock cycles (68.0%)
+	    time needed for relocation: 25601766 clock cycles (74.9%)
-        number of relative relocations: 73592
+        number of relative relocations: 0
-	   time needed to load objects: 8138088 clock cycles (29.0%)
+	   time needed to load objects: 7724814 clock cycles (22.6%)

https://lists.fedoraproject.org/pipermail/devel/2013-October/190274.html

Comment 1 Jakub Jelinek 2013-10-21 06:46:22 UTC
Can't reproduce. Additionally, rpmfusion mplayer is a PIE, so it isn't prelinked at all, and while some libraries it is linked against can be prelinked, the dynamic linker ignores their prelink assigned addresses (like with LD_USE_LOAD_BIAS=0) and thus they are treated the same, relative relocations can't be skipped in that case like they can't be skipped with non-prelinked system etc.

Comment 2 Jaroslav Reznik 2015-03-03 15:09:21 UTC
This bug appears to have been reported against 'rawhide' during the Fedora 22 development cycle.
Changing version to '22'.

More information and reason for this action is here:
https://fedoraproject.org/wiki/Fedora_Program_Management/HouseKeeping/Fedora22

Comment 3 Fedora End Of Life 2016-07-19 10:30:12 UTC
Fedora 22 changed to end-of-life (EOL) status on 2016-07-19. Fedora 22 is
no longer maintained, which means that it will not receive any further
security or bug fix updates. As a result we are closing this bug.

If you can reproduce this bug against a currently maintained version of
Fedora please feel free to reopen this bug against that version. If you
are unable to reopen this bug, please file a new report against the
current release. If you experience problems, please add a comment to this
bug.

Thank you for reporting this bug and we are sorry it could not be fixed.