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Full Discussion: Unix message Queue
Top Forums UNIX for Advanced & Expert Users Unix message Queue Post 38919 by Perderabo on Wednesday 30th of July 2003 11:12:50 AM
Old 07-30-2003
Hmmm....you do have a point. I was getting CBYTES mixed up with QBYTES.

I agree, for the most part, QNUM = 0 and CBYTES != 0 is not consistent. But I can think of one exception where it might make sense. When you do your msgsnd, you are setting msgflg to zero. That means that IPC_NOWAIT is turned off. The msgsnd system call checks to see if this message would exceed some limits. This includes a check of the message queue you are using as well as some system wide limits. If a msgsnd would exceed a limit and it did not set IPC_NOWAIT, the msgsnd system call will suspend until it is safe to send the message. I don't know what state the message queue is in during this suspension. It could well be that CBYTES has been increased but QNUM has not yet been incremented.

This would explain why it works for a few hours and then locks up. Reproduce the error and then run "ipcs -qa" and compare the total messages queue resources in use against your kernel parameters. If this is the problem, you will need to increase the kernel parameters. Or you may have a message queue leak somewhere.

That is my only idea. If it's not that, I would next suspect a broken kernel. You might check for any appropiate patches.
 

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RT::Client::REST::Queue(3pm)				User Contributed Perl Documentation			      RT::Client::REST::Queue(3pm)

NAME
RT::Client::REST::Queue -- queue object representation. SYNOPSIS
my $rt = RT::Client::REST->new(server => $ENV{RTSERVER}); my $queue = RT::Client::REST::Queue->new( rt => $rt, id => 'General', )->retrieve; DESCRIPTION
RT::Client::REST::Queue is based on RT::Client::REST::Object. The representation allows one to retrieve, edit, comment on, and create queue in RT. Note: RT currently does not allow REST client to search queues. ATTRIBUTES
id For retrieval, you can specify either the numeric ID of the queue or its name (case-sensitive). After the retrieval, however, this attribute will be set to the numeric id. name This is the name of the queue. description Queue description. correspond_address Correspond address. comment_address Comment address. initial_priority Initial priority. final_priority Final priority. default_due_in Default due in. DB METHODS
For full explanation of these, please see "DB METHODS" in RT::Client::REST::Object documentation. retrieve Retrieve queue from database. store Create or update the queue. search Currently RT does not allow REST clients to search queues. QUEUE-SPECIFIC METHODS tickets Get tickets that are in this queue (note: this may be a lot of tickets). Note: tickets with status "deleted" will not be shown. Object of type RT::Client::REST::SearchResult is returned which then can be used to get to objects of type RT::Client::REST::Ticket. INTERNAL METHODS
rt_type Returns 'queue'. SEE ALSO
RT::Client::REST, RT::Client::REST::Object, RT::Client::REST::SearchResult, RT::Client::REST::Ticket. AUTHOR
Dmitri Tikhonov <dtikhonov@yahoo.com> LICENSE
Perl license with the exception of RT::Client::REST, which is GPLed. perl v5.14.2 2012-01-20 RT::Client::REST::Queue(3pm)
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