slowness printing on AIX

[Amy Tanner]

We've recently noticed a significant performance issue when printing on our AIX boxes that we do not see on our Solaris boxes.  First, here are the particulars of our environment:

cups server:
SuSE 10
cups 1.1.23
10.4 VLAN
~1200 printers configured

cups clients:
Solaris 8 or Solaris 9 running cups 1.1.23, 10.1 VLAN
AIX 5.3 running cups 1.1.23, 10.1 VLAN

Printing /etc/motd on a Solaris box takes about 2 seconds.  Printing the same /etc/motd on an AIX boxes takes about 30 seconds.  Similar slowness can be duplicated by just issuing an lpstat command as well.

I have system call output from truss I can send. The output looks the same on Solaris as on AIX, yet there's this significant time difference.  The cups clients are configured the same in both environments.  They are configured to go directly to a print server (we are not using the broadcast option).

We did try recompiling cups 1.1.23 with gcc 4.0 but the end results were the same.  We also tried turning on polling, which did seem to improve performance some.  However, the polling process itself takes about 25 minutes to run each time and chews up a lot of CPU during that time. We are also considering adding a 2nd interface on our cups server for the 10.1 VLAN so we could try the broadcast method.  Any opinions on this would be appreciated.

Any ideas?  Let me know if the truss output or any other information would be helpful to send.

Thank you.