Bug 120943 - kscd eats lots of memory
Summary: kscd eats lots of memory
Status: RESOLVED WORKSFORME
Alias: None
Product: SUSE LINUX 10.0
Classification: openSUSE
Component: KDE (show other bugs)
Version: RC 4
Hardware: x86-64 All
: P5 - None : Major
Target Milestone: ---
Assignee: E-mail List
QA Contact: E-mail List
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2005-10-07 07:46 UTC by Olaf Kirch
Modified: 2006-05-07 11:35 UTC (History)
0 users

See Also:
Found By: Development
Services Priority:
Business Priority:
Blocker: ---
Marketing QA Status: ---
IT Deployment: ---

Attachments
strace (I left it running for a while) (541.11 KB, text/plain)
2005-10-07 07:48 UTC, Olaf Kirch 		Details
View All Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.
Description Olaf Kirch 2005-10-07 07:46:09 UTC 
After starting kscd, I noticed that my system got a little sluggish  
every now and then (even with no CD in the drive).  
  
I watched the system with top and noticed that kcsd's resident memory  
size would sometimes jump to almost 1GB of memory. It seems it mmaps 
a 1G region and walks all over it, then releases it. 
 
I'm attaching an strace of kscd demonstrating the problem.
Comment 1 Olaf Kirch 2005-10-07 07:48:37 UTC 
Created attachment 51749 [details]
strace (I left it running for a while)

The relevant bit are the frequent mmap/munmap calls:

mmap(NULL, 1023414272, PROT_READ|PROT_WRITE,
		MAP_PRIVATE|MAP_ANONYMOUS, -1, 0)
...
munmap(0x2aaaafa00000, 1023414272)

I hope the KDE folks can tell me why it's doing this.
Comment 2 Stephan Kulow 2005-10-07 08:14:13 UTC 
hmm, there is no mmap call in the kscd code from what grep tells me. Am I free 
to blame glibc here? :)
Comment 3 Lubos Lunak 2005-10-07 09:12:24 UTC 
Probably not. The mmap() may come from malloc().
Comment 4 Dirk Mueller 2005-10-07 09:27:57 UTC 
its most likely a malloc because its an anon mmap. anyway, this is probably  
x86_64 specific, and I don't have such a computer available for testing.   
  
Olaf, please set ulimit -v 300000, install debuginfo packages, wait till kscd  
crashes and attach the backtrace please.   
  
<insert standard rambling about missing ulimits on a default suse 
installation>
Comment 5 Stephan Kulow 2006-05-07 11:35:06 UTC 
we were unable to reproduce