Re: Re: LPRng: LPRng-3.8.27: strange load problem
Hi patrick, thats not the the problem. we have 6 boxes that do the same data processing. we move data via lpr. occationaly 1 lprngqueue stops working. the problem can be solved via start/stop lpd. simply jobs dont get processed anymore. we tried a lot to find the problem but it seems to happen only if nobody watches. The daemon still accepts jobs, does not show any odd bahavier other than stop processsing the queue (no zombies, no lots of worker processes). It seems related to the systemload but perhaps its only because more jobs arrive. Last month we had no problems this month more than 3 times. (but all independent) We had more problems when the backup (rsync) run but since its complex to do i will try to reproduce it next week. regards, walter ps: how much would it cost to solve ? - - - - - - - - - - - - - - Original Message - - - - - - - - - - - - - - From: Patrick Powell [EMAIL PROTECTED] Subject: Re: LPRng: LPRng-3.8.27: strange load problem Date: 10/05/04 19:00 From [EMAIL PROTECTED] Thu Sep 30 16:19:20 2004 Date: Wed, 29 Sep 2004 10:45:01 +0200 To: [EMAIL PROTECTED] From: [EMAIL PROTECTED](Walter Harms) Subject: LPRng: LPRng-3.8.27: strange load problem Hi Patrik, i have a strange problem when the lpd has some load, sometimes (lets say 1:50 change) he suddely stops without any errormessage or other indication whats going on. I have tried to reproduce the error but failed so far. are you aware of this problem ? regards, walter When you say 'stop', do you mean it stops accepting jobs OR it does not process any jobs that are in the queue? To prevent denial of service attacks, LPRng will not fork more than a specified number of 'worker' processes at a time. It is assumed that doing so will cause the operating system to be unable to start additional processes. This 'high water mark' is controlled by: # Purpose: maximum number of servers that can be active # default max_servers_active=1024 (INTEGER) - YOU MUST BE A LIST MEMBER IN ORDER TO POST TO THE LPRng MAILING LIST The address you post from or your Reply-To address MUST be your subscription address If you need help, send email to [EMAIL PROTECTED] (or lprng-requests or lprng-digest-requests) with the word 'help' in the body. To subscribe to a list with name LIST, send mail to [EMAIL PROTECTED] with: | example: subscribe LIST mailaddr | subscribe lprng-digest [EMAIL PROTECTED] unsubscribe LIST mailaddr | unsubscribe lprng [EMAIL PROTECTED] If you have major problems, call Patrick Powell or one of the friendly staff at Astart Technologies for help. Astart also does support for LPRng. Also, check the Web Page at: http://www.lprng.com for any announcements. Astart Technologies (LPRng - Print Spooler http://www.lprng.com) 6741 Convoy Court San Diego, CA 92111 858-874-6543 FAX 858-751-2435 -
Re: LPRng: LPRng-3.8.27: strange load problem
From [EMAIL PROTECTED] Thu Sep 30 16:19:20 2004 Date: Wed, 29 Sep 2004 10:45:01 +0200 To: [EMAIL PROTECTED] From: [EMAIL PROTECTED](Walter Harms) Subject: LPRng: LPRng-3.8.27: strange load problem Hi Patrik, i have a strange problem when the lpd has some load, sometimes (lets say 1:50 change) he suddely stops without any errormessage or other indication whats going on. I have tried to reproduce the error but failed so far. are you aware of this problem ? regards, walter When you say 'stop', do you mean it stops accepting jobs OR it does not process any jobs that are in the queue? To prevent denial of service attacks, LPRng will not fork more than a specified number of 'worker' processes at a time. It is assumed that doing so will cause the operating system to be unable to start additional processes. This 'high water mark' is controlled by: # Purpose: maximum number of servers that can be active # default max_servers_active=1024 (INTEGER) Note that this is, by default, 1024 (default). You might want to try lowering this to (say) 512 and see if this effects anything. The problem here is that when the system goes into a heavy load, lprng does not notice this, but tries to perform as normal. The problem usually is noticed by processes that it 'forks', which then desperately try to fork subprocesses, which do not work, which, after a while, (10 minutes), the worker process exits, LPRng sees the exit process, decides it can now do more work, and MAY start a subprocess. To ensure that this does not become a 'permanent' condition, periodically LPRng will do a scan of print queues, looking for work. This scanning is done by ONE process, which will send a message to the master LPD process, which keeps a list of all the queues which need work. When the load goes down, this 'queue list' is scanned for the oldest entry, and a subprocess is forked to handle this. Umm... if a large number of queues are ready to be serviced, the lpd server might try to start a lot of them, leading to the same problem as before. As I say, this usually only occurs under a very high load condition with a lot of processes being created and then not exiting. I have observed with on several Web Servers running Apache and CGI scripts. Patrick Patrick Powell Astart Technologies [EMAIL PROTECTED]6741 Convoy Court Network and System San Diego, CA 92111 Consulting 858-874-6543 FAX 858-751-2435 LPRng - Print Spooler (http://www.lprng.com) - YOU MUST BE A LIST MEMBER IN ORDER TO POST TO THE LPRng MAILING LIST The address you post from or your Reply-To address MUST be your subscription address If you need help, send email to [EMAIL PROTECTED] (or lprng-requests or lprng-digest-requests) with the word 'help' in the body. To subscribe to a list with name LIST, send mail to [EMAIL PROTECTED] with: | example: subscribe LIST mailaddr | subscribe lprng-digest [EMAIL PROTECTED] unsubscribe LIST mailaddr | unsubscribe lprng [EMAIL PROTECTED] If you have major problems, call Patrick Powell or one of the friendly staff at Astart Technologies for help. Astart also does support for LPRng. Also, check the Web Page at: http://www.lprng.com for any announcements. Astart Technologies (LPRng - Print Spooler http://www.lprng.com) 6741 Convoy Court San Diego, CA 92111 858-874-6543 FAX 858-751-2435 -
LPRng: LPRng-3.8.27: strange load problem
Hi Patrik, i have a strange problem when the lpd has some load, sometimes (lets say 1:50 change) he suddely stops without any errormessage or other indication whats going on. I have tried to reproduce the error but failed so far. are you aware of this problem ? regards, walter - YOU MUST BE A LIST MEMBER IN ORDER TO POST TO THE LPRng MAILING LIST The address you post from or your Reply-To address MUST be your subscription address If you need help, send email to [EMAIL PROTECTED] (or lprng-requests or lprng-digest-requests) with the word 'help' in the body. To subscribe to a list with name LIST, send mail to [EMAIL PROTECTED] with: | example: subscribe LIST mailaddr | subscribe lprng-digest [EMAIL PROTECTED] unsubscribe LIST mailaddr | unsubscribe lprng [EMAIL PROTECTED] If you have major problems, call Patrick Powell or one of the friendly staff at Astart Technologies for help. Astart also does support for LPRng. Also, check the Web Page at: http://www.lprng.com for any announcements. Astart Technologies (LPRng - Print Spooler http://www.lprng.com) 6741 Convoy Court San Diego, CA 92111 858-874-6543 FAX 858-751-2435 -
