Questions tagged [mqueue]

10 questions
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Multiqueue tun/tap interface

I am trying to understand how Multiqueue tuntap interface works. Following the instructions provided at: https://www.kernel.org/doc/Documentation/networking/tuntap.txt I was able to create multiple queues. However, I don't know how to check the…
Deys Nima
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How to check usage of mqueues reliably?

I run a testing server for software that depends on the massive usage of mqueues (POSIX messages queues). I increased limits to a reasonable level and got it working a long time ago. However, the number of tests (and their mqueues) keeps rising and…
Melebius
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Timeout Error while using Command Queue

I am new to command queue mechanism in Linux. I am using the following: Kernel Tree: git clone https://android.googlesource.com/kernel/msm Kernel Ver: 4.9.96 While doing read/write I observe a timeout error: mmc0: request with tag: 30 flags:…
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Equivalent of /dev/mqueue to enumerate SysV message queues

Linux supports two kinds of message queues: POSIX (i.e., those created by mq_open), and System V (i.e., those created by msgget). For POSIX message queues, mq_overview(7) documents that you can enumerate them via the mqueue virtual filesystem,…
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Why is the limit for POSIX message queues so low?

Was going to use a bunch of message queues to communicate between different threads in two processes, but it appears that the max is 10 (Ubuntu 18.10). Just wondering what the reason is for not having this default max number of message queues…
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1 answer

Remove specific emails from sendmail mqueue

How do I remove emails from mqueue based on destination address. Needing to remove deferred messages going to "[email protected]" Due to an endless loop (that has been found and corrected) I have a huge amount of emails deferred or qued for…
Sarah
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Ran a program as root on accident and now my mq-open cmd's fail with Permisson Denied

Ok so I wanted to know where to see the actual message queue files in a linux system? I have a program that was compiled and ran containing message queues but I ran the program as root by accident and now after running as a regular un privileged…
MacLCM
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Check if fs.mqueue.msg_max must be increased and do it

I need to run a program with a bash script. This program may require a larger than default message queue. I know I can increase it with: sudo sysctl fs.mqueue.msg_max=3000 And I could, for instance, check it with: echo "$(sysctl…
Mefitico
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Why do some multiqueue (qdisc mq) have n tx / 1 rx, while others have 1 tx / n rx?

While trying to understand multiqueue queuing disciplines (mq qdisc), I stumbled across the following configs : On my laptop, my WiFi interface implements a mq qdisc with 1 rx and 4 tx : $ sudo tc qdisc list dev wlp2s0 qdisc mq 0: root …
ChennyStar
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Handling multiple messages in message queue

I've done some research about this topic but I didn't understand it quite well. From msgsnd man page : The msgsnd() system call appends a copy of the message pointed to by msgp to the message queue whose identifier is specified by…
Zeno Raiser
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