Re: slapd stops working when machine becomes CPU bound (ITS#3149)

[jblack@inframix.com]

On Tue, May 18, 2004 at 04:04:21PM -0700, Kurt D. Zeilenga wrote:
> It's unclear from the information you provide whether the behavior you
> describe is due to a bug in OpenLDAP Software or due to some other
> problem (a bug elsewhere, or a configuration problem).
> 
> I suggest you try to isolate the problem.  I suggest you start by
> using OpenLDAP clients (e.g., ldapsearch(1)) to reproduce the behavior
> instead of involving non-OpenLDAP clients.

root@neptune:~# time ldapsearch -x |wc -l
2949

real    0m0.098s
user    0m0.015s
sys     0m0.009s

root@neptune:~# ./main & time ldapsearch -x | wc -l
[1] 20258
2949

real    1m7.241s
user    0m0.006s
sys     0m0.002s


Here is an is an strace of when ldapsearch -x gets stuck the first time:

select(1024, [3], [], NULL, NULL)       = 1 (in [3])
read(3, "0j\2\1\2de\4", 8)              = 8
read(3, "!ou=ArchProjects,dc=gnuarch,dc=o"..., 100) = 100
write(1, "\n", 1)                       = 1
write(1, "# ArchProjects, gnuarch.org\n", 28# ArchProjects, gnuarch.org
) = 28
write(1, "dn: ou=ArchProjects,dc=gnuarch,d"..., 38dn:
ou=ArchProjects,dc=gnuarch,dc=org) = 38
write(1, "ou: ArchProjects\n", 17ou: ArchProjects)      = 17
write(1, "objectClass: top\n", 17objectClass: top)      = 17
write(1, "objectClass: organizationalUnit\n", 32objectClass:
organizationalUnit) = 32
select(1024, [3], [], NULL, NULL


Other software appears to run as expected, unless pam is involved, in
which case that software blocks too .

> This issue will be moved to Feedback state pending details which
> more clearly shows the behavior is due to a bug in OpenLDAP Software.

I'm more than willing to provide information and accounts as necessary to
debug this.

Thank you very much for helping out,
James

> 
> Kurt
> 
> At 12:40 PM 5/18/2004, jblack@inframix.com wrote:
> >Full_Name: James Blackwell
> >Version: 2.1.29
> >OS: Debian GNU
> >URL: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=245014
> >Submission from: (NULL) (209.173.6.55)
> >
> >
> >On my Debian GNU/sid machine, slapd stops serving if any user runs the
> >following: 
> >
> >$ renice 19 $$; while [ 1==1 ]; do echo -n ""; done
> >
> >The result of this command, run by *any* user logged in, is that nobody else can
> >log in.
> >
> >A better example is that if a user compiles and runs the following code, nobody
> >can log in:
> >
> >int main() { while(1) {} return 0; }

-- 
James Blackwell          Please do not send me carbon copies of mailing
Smile more!              list posts. Such mail is unsolicited. Thank you!

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