Subject: Re: 3.0 YP lookup latency
To: None <tech-net@netbsd.org>
From: Christos Zoulas <christos@astron.com>
List: tech-net
Date: 06/20/2006 19:31:40
In article <200606201808.k5KI8r7V011237@egsner.cirr.com>,
Stephen M. Jones <smj@cirr.com> wrote:
>I'm working out a migration to 3.0 and have setup a client machine for
>testing with the 3.0 base release from December and a new kernel from
>the May 27th source build.
>
>I've tried setting up the 3.0 host as a yp client and a slave from the
>master, but I'm still seeing a 15 or so second latency on uid mapping.
>However, ypcat requests return as quickly as expected. The ypserver and
>slave are both NetBSD 2.1, but I'm not sure how this could be an issue.
>
>So I turned on logging on the ypserver and discovered that any yp lookup
>(using id, whoami, sudo et cetera) would trigger a next_2: request for
>every single user id in the password file. This explains the latency.
>
>Is this a bug or an incompatibility? I won't be able to upgrade my
>ypserver and ypslave for a couple of months, and if its an incompatibility
>I would assume it would be resolved once everyone is happily running
>3.0. I actually tried copying over the 'ypbind' from the 2.1 system to
>the 3.0 and restarting it, but I get the same results.
>
>$ time id smj
>load: 0.35 cmd: id 16846 [poll] 0.12u 0.20s 0% 1472k
>load: 0.35 cmd: id 16846 [poll] 0.24u 0.41s 2% 1472k
>load: 0.35 cmd: id 16846 [poll] 0.43u 0.69s 4% 1472k
>load: 0.32 cmd: id 16846 [poll] 0.53u 0.84s 4% 1472k
>load: 0.32 cmd: id 16846 [poll] 0.58u 0.93s 5% 1472k
>uid=1001(smj) gid=0(wheel)
>groups=0(wheel),500(arpa),800(instructor),600(MetaARPA)
> 16.16s real 1.65s user 2.65s system
I think that this is an issue with the rpc library. I forget the exact
bug report now. Do you have the same problem in current?
christos