Hi Justin,
Attached is a link to the dtrace script we wrote for the sparks project to 
monitor
requests going to/from nscd.  We have a couple of variations on the theme,
plus a few others that we still need to post to the sparks /dtrace page.

We also are working with someone who is working on a set of USDT probes
for some of the key internal components of our nss_ldap name service switch.

The script is here:
http://www.opensolaris.org/os/project/sparks/dtrace/nscd.d

Current sparks dtrace news, scripts or other updates can be found here:
http://www.opensolaris.org/os/project/sparks/dtrace/
the Sparks project is:
http://www.opensolaris.org/os/project/sparks/

If you gather any performance information that may be helpful, please let us 
know
on the sparks-discuss alias or forward it to me.  I will see that the 
performance
problem gets looked into.

Thanks again,
Doug.


Nicolas Williams wrote:
> ----- Forwarded message from Justin Lloyd <[EMAIL PROTECTED]> -----
> 
> Date: Wed, 21 May 2008 11:50:50 -0600
> From: Justin Lloyd <[EMAIL PROTECTED]>
> Subject: [dtrace-discuss] Slow pkginstalls due to long door_calls to nscd
> To: [email protected]
> 
> Hi all,
> 
> I am installing a zone onto two different V445s running S10U4 and the
> zones are taking hours to install (about 1000 packages), that is, the
> problem is identical on both systems. A bit of trussing and dtracing has
> shown that the pkginstalls being run by the zoneadm install are making
> door_call calls to nscd that are taking very long, so far observed to be
> 5 to 40 seconds, but always in times divisible by 5 seconds (5, 10, 15,
> etc.), leading to the thought that it is one or more name service
> timeouts. Eventually, once the door_calls finish, the actual package
> install is very quick.
> 
> There may be a simple misconfiguration on both systems, but I can't
> figure out what that might be. Additionally, I don't know why the
> pkginstalls are making door_calls to begin with, and I'm not sure how to
> figure that out. So that's one my main question:
> 
>    *** How can I find out exactly what the pkginstalls are asking nscd
> to resolve? ***
> 
> Hopefully that will lead me (and the Sun engineer with whom I have a
> case open) to an understanding of what is leading to the presumed
> timeouts.
> 
> FWIW, here's a partial truss with timestamps of an existing pkginstall
> process. Once it hit the ioctl(3,...) it flew through the package
> installation. Note the times around the door_calls: 13, 10 and 15
> seconds (the first isn't a multiple of 5 since I started the truss
> during the call).
> 
> Base time stamp:  1210181159.9172  [ Wed May  7 17:25:59 GMT 2008 ]
> door_call(4, 0xFFBFD030)        (sleeping...)
> 1210472.1302    door_call(4, 0xFFBFD030)                        = 0
> 1210472.1306    open("/dev/udp6", O_RDONLY)                     = 5
> 1210472.1310    ioctl(5, SIOCGLIFNUM, 0xFFBFD2DC)               = 0
> 1210472.1312    close(5)                                        = 0
> 1210472.1312    getuid()                                        = 0 [0]
> 1210472.1313    getuid()                                        = 0 [0]
> 1210472.1314    door_info(4, 0xFFBFCF88)                        = 0
> door_call(4, 0xFFBFD030)        (sleeping...)
> 1210482.1503    door_call(4, 0xFFBFD030)                        = 0
> 1210482.1505    getuid()                                        = 0 [0]
> 1210482.1505    getuid()                                        = 0 [0]
> 1210482.1506    door_info(4, 0xFFBFCF88)                        = 0
> door_call(4, 0xFFBFD030)        (sleeping...)
> 1210497.1802    door_call(4, 0xFFBFD030)                        = 0
> 1210497.1804    ioctl(3, (('m'<<8)|7), 0xFFBFD8EC)              = 0
> 
> Thanks,
> Justin
> 
> 
> _______________________________________________
> dtrace-discuss mailing list
> [email protected]
> 
> 
> ----- End forwarded message -----
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