Delay in print processing may cause print jobs not to finish in time
This document (000020365) is provided subject to the disclaimer at the end of this document.
Environment
SUSE Linux Enterprise Server 15 SP2
Situation
Resolution
Cause
The issue was identified by the upstream cups project and a fix was introduced in cups-2.2.8:
The cupsCreateJob, cupsPrintFile2, and cupsPrintFiles2 APIs did not use the supplied HTTP connection (Changelog )
Status
Additional Information
When looking at an strace output of an lpr command, a high number of recvfrom is seen:
localhost:~ # strace -c lpr -Ppdfprint /etc/hosts
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
99.96 0.613015 1 451790 5 recvfrom
[...]
------ ----------- ----------- --------- --------- ----------------
100.00 0.613264 452291 19 total
The code was changed from using cupsEnumDests (which called cups_create_cb a very high amount of times to get the destination of a printer) to cupsGetNamedDest which reduced the number of calls tremendously.
After installing the fix:
localhost:~/PTF-1189517-cups_slow # strace -c lpr -Ppdfprint /etc/hosts
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
95.50 0.008879 1 5580 4 recvfrom
[...]
------ ----------- ----------- --------- --------- ----------------
100.00 0.009297 6018 20 total
Please note: Above values have been captured on a test system and may not reflect production systems!
Disclaimer
This Support Knowledgebase provides a valuable tool for SUSE customers and parties interested in our products and solutions to acquire information, ideas and learn from one another. Materials are provided for informational, personal or non-commercial use within your organization and are presented "AS IS" WITHOUT WARRANTY OF ANY KIND.
- Document ID:000020365
- Creation Date: 19-Aug-2021
- Modified Date:15-Sep-2021
-
- SUSE Linux Enterprise Server
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