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Questions tagged [qos]

Quality-Of-Service (QoS) is the management of system resources, network or otherwise, to apply greater returns with minimal overhead, providing a measurable increase in performance.^1 ^2 ^3

Application QoS is related to thread management or Interprocess Communication (IPC) management as it relates to hardware and software resource access.

"In the field of computer networking and other packet-switched telecommunication networks, quality of service refers to traffic prioritization and resource reservation control mechanisms rather than the achieved service quality. Quality of service is the ability to provide different priorities to different applications, users, or data flows, or to guarantee a certain level of performance to a data flow."

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amqp_basic_qos not having any effect

I am trying to code a simple consumer using librabbitmq. It is working, but when I do execute amqp_basic_consume, it consumes the entire queue. What I want is for it to get a single message, process it and repeat. I tried using a basic_qos to have…
Brian Andrus
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Since MQTT based on TCP, then why MQTT need QoS ?

MQTT is a protocol based on TCP, and, TCP is a reliable transfer protocol. Since TCP is reliable, then why there's a level 0 QoS in MQTT which represent message from publisher to receiver may lost ? Or more, since TCP naturally supports reliable…
chenxinlong
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How can I test an internet connection during a certain period of time?

I would like to test the internet connection of some place. Therefore I want to write my own script which is triggered every some random minutes to do some stuff. I was thinking about: Getting the latency until I ping some big site. Downloading a…
nck
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Is a QoS2 massage delivery considered as processed when the PUBCOMP is missing?

With a four-part handshake (a MQTT QoS level 2 transmission) the last acknowledge message is the PUBCOMP messsage. Following presumptions are made: The PUBCOMP messsage is sent from the receiver after it processes the message payload and delivers…
cheneym
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Kubernetes default QoS for whole namespace

Is there any method of setting default QoS for all of the nodes from given namespace? Or just set QoS on namespace level instead of pod level. I mean the situation where every existing and every newly created pod will have this default setting for…
parasit
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Iperf flow is not assigned to queue

I'm new to ryu rest QoS. I'm trying to create QoS queue and divide bandwith link to two iperf flows. First flow max-rate is 300Kbps. Second flow min-rate is 700Kbps. Link bandwith is 1Mbps. Problem is both flow are using circa half…
Torrado36
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Linux: HTB + PRIO qdisc: sometimes empty PRIO 1 queue

I am facing a behaviour I can't explain myself at the moment. Here is what I am trying to do: limit the sending rate through an interface (enp0s8) and apply a PRIO qdisc. Packets are sent to the appropriate band of the PRIO qdisc following their…
avan
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Basic QoS Algorithm?

I have a continuous loop sending packets like so from a ConcurrentQueue: ConcurrentQueue queue = new ConcurrentQueue(); while(true){ packet data; if (!queue.TryPeek(out packet)) continue; send(data); …
Tod
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Any relationship between " tc " command and /user/src/kernel-source/net/sched in the Linux kernel

I want to know some basic of Traffic Control in the Linux kernel . I downloaded Linux kernel source code and i can see scheduling algorithms are present in /user/src/kernel-source/net/sched After that i tried about setting Queuing discipline…
user2986042
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MQTT qos 2 timeout between PUBREC and PUBREL

Is there some timeout mechanism for MQTT between PUBREC and PUBREL in QOS 2? Or the timeout is same as global keep alive timeout? Thanks! Diagram from HiveMQ (http://www.hivemq.com/blog/mqtt-essentials-part-6-mqtt-quality-of-service-levels)
Asoul
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DDS reliable reader getting same messages on application restart

I have an RTI DDS application with a reliable reader and reliable writer. Whenever I restart the reader application, the reader reads messages it already received. So in the case the reader received a message to restart the application it is now in…
jgr208
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MQTT QoS2 why use 4 packets?

I think we can just use publish and pubrcv to meet the QoS2. ClientA-> Server publish packet Server -> ClientA pubrecv packet When the server recv the publish packet, save to db, then the server publish to other clients, eg. ClientB. Even if we…
user501836
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sending qos parameter along with MQTT notification

I am using ponte node application for sending MQTT notification from web to devices and please see below the format I am using. "http://www.example.com/resources/topic/" and message as body while testing from postman. My question is how can i send…
Tismon Varghese
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Multicast address in code not getting set in DDS code

I have the following code in my DDS program for java 8 using RTI DDS 5.2.0 DomainParticipantFactory.PARTICIPANT_QOS_DEFAULT. discovery.initial_peers.add("239.255.0.50"); DomainParticipantFactory.PARTICIPANT_QOS_DEFAULT. …
jgr208
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Extract QoS control value from .pcap file

I need to implement .pcap parser for QoS values analyzing. The problem is to open .pcap-file (generated by Wireshark or tcpdump) and extract QoS Control value (if available) from each package. I know that QoS Control located inside IEEE 802.11 QoS…
olpo.graphy
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