Subject: PostgreSQL, NetBSD and NFS
To: None <pgsql-hackers@postgreSQL.org>
From: D'Arcy J.M. Cain <darcy@druid.net>
List: current-users
Date: 01/30/2003 10:43:32
I have posted before about this but I am now posting to both NetBSD and 
PostgreSQL since it seems to be some sort of interaction between the two.  I 
have a NetAPP filer on which I am putting a PostgreSQL database.  I run 
PostgreSQL on a NetBSD box.  I used rsync to get the database onto the filer 
with no problem whatsoever but as soon as I try to open the database the NFS 
mount hangs and I can't do any operations on that mounted drive without 
hanging.  Other things continue to run but the minute I do a df or an ls on 
that drive that terminal is lost.

On the NetBSD side I get a "server not responding" error.  On the filer I see 
no problems at all.  A reboot of the filer doesn't correct anything.

Since NetBSD works just fine with this until I start PostgreSQL and 
PostgreSQL, from all reports, works well with the NetApp filer, I assume that 
there is something out of the ordinary about PostgreSQL's disk access that is 
triggering some subtle bug in NetBSD.  Does the shared memory stuff use disk 
at all?  Perhaps that's the difference between PostgreSQL and other 
applications.

The NetApp people are being very helpful and are willing to follow up any 
leads people might have and may even suggest fixes if necessary.  I have 
Bcc'd the engineer on this message and will send anything I get to them.

-- 
D'Arcy J.M. Cain <darcy@{druid|vex}.net>   |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 425 1212     (DoD#0082)    (eNTP)   |  what's for dinner.