cups-polld uses 99% cpu time

[Michael De Vlaminck]

angelb wrote:
>>Michael De Vlaminck wrote:
>>
>>>angelb wrote:
>>>
>>>>>Hello,
>>>>>
>>>>>I've configured a cups printsystem with 2 servers and about 200 clients
>>>>>connecting via cups 1.1 and samba.
>>>>>The clients are configured to poll the 2 servers for printers. But one
>>>>>server cups-server is the main server. The other one cups-backup is the
>>>>>backup server. But cups isn't running on cups-backup due to issues with
>>>>>the accounting system we use.
>>>>>So the clients poll there printers from cups-server and get a 'unknown
>>>>>host' error.
>>>>>We went "live" this morning and by now we had about 10 complaints that
>>>>>the cups-polld process uses 99% cpu time. After taking a closer look it
>>>>>seems like it was the poll process which polls cups-server (the one
>>>>>that
>>>>>is running) is the one uses that much cpu time.
>>>>>
>>>>>What can be the cause of this?
>>>>>
>>>>>thanks in advance
>>>>>
>>>>>Michael De Vlaminck
>>>>
>>>>
>>>>Quick fix: upgrade or install CUPS 1.2.1
>>>>
>>>>I've also ran into the same issue and CUPS 1.2 appears to have the
>>>>fix.
>>>>
>>>>Good luck.
>>>>
>>>>Angel
>>>>
>>>>
>>>
>>>is there also a way do fix it without upgrading?
>>>
>>>thx
>>>Michael
>>>_______________________________________________
>>>cups mailing list
>>>cups at easysw.com
>>>http://lists.easysw.com/mailman/listinfo/cups
>>
>>Or perhaps instead of polling the server you should relay the
>>printer packets to the subnets of the clients and have
>>them listen for the packets. Just a thought.
>>
> 
> 
> It doesn't matter whether you're using polling, browsing, or relaying,
> the clients will still have to process the incoming packets. It is in
> that process that causes CPU to spike specially in a large environment.
> 
> I've never really had problems with 200+ printers on a client but when
> we have more than 500, you'll see a significant CPU use. If you have
> more than 1000+ printers, then you'll in for it big-time; you may have
> to poll only once-a-day preferrably when the system is most idle.
> 
> I'm putting a lot of faith into CUPS 1.2 but at the moment, my testing
> hasn't gone well. Clients(AIX and Solaris) polling crashes while
> polling the server. I've submitted an STR but I hope it's just an error
> in my configuration...well soon see.
> 
> Like most users, I was hoping there was a fix to this in 1.1 but it's
> addressed only in 1.2....correct me if I'm wrong.
> 
> Angel

the problem is that the cups-polld process on the clients uses all cpu 
time. the cupsd process on the server needs about 10-40% cpu time but I 
suppose that that's normal.

If we change our configuration so that polling isn't used, instead we 
use client.conf. Will that solve our problem?

Michael