Print dialog polls print-server for printers several times per second
Submitted by kor..@..il.com
Link to original bug (#711446)
Description
How to reproduce:
- Enable debugging in CUPS by editing this line in /etc/cups/cupsd.conf: LogLevel debug
- Restart CUPS with sudo restart cups
- Open a GTK+ application and press Ctrl+P to show Print dialog (for example, evince or eog).
- Notice that CUPS is polled two or three times per second for printer list: grep CUPS-Get-Printers /var/log/cups/error_log
- Just to compare, open Chromium browser and press Ctrl+P to print with Chromium's own print dialog. Notice how Chromium enumerates printers only once.
Tested on Ubuntu 12.04 x64 with libgtk-3-0 3.4.2, eog 3.4.2, evince 3.4.0. If you open three apps and press Ctrl+P in each, print-server will be polled three times more frequently.
This behavior puts unnecessary strain on print-servers, especially if they serve hundreds or thousands of clients in enterprise environment.
Is there a way to adjust this polling interval?
Excerpt from CUPS error_log: D [04/Nov/2013:17:57:21 -0500] cupsdReadClient: 13 1.1 CUPS-Get-Printers 1 D [04/Nov/2013:17:57:21 -0500] Returning IPP successful-ok for CUPS-Get-Printers (no URI) from localhost D [04/Nov/2013:17:57:21 -0500] cupsdReadClient: 13 1.1 CUPS-Get-Printers 1 D [04/Nov/2013:17:57:21 -0500] Returning IPP successful-ok for CUPS-Get-Printers (no URI) from localhost D [04/Nov/2013:17:57:21 -0500] cupsdReadClient: 13 1.1 CUPS-Get-Printers 1 D [04/Nov/2013:17:57:21 -0500] Returning IPP successful-ok for CUPS-Get-Printers (no URI) from localhost D [04/Nov/2013:17:57:22 -0500] cupsdReadClient: 13 1.1 CUPS-Get-Printers 1
Version: 3.10.x