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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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Is DispatchQueue.global(qos: .userInteractive).async same as DispatchQueue.main.async

I was going through the tutorial : https://www.raywenderlich.com/148513/grand-central-dispatch-tutorial-swift-3-part-1 And came across the definition of QoS class User-interactive. Its mentioned there that this should run on main thread. So, my…
Nishu_Priya
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Understanding mqtt subscriber qos

I am new to MQTT and I just learned about the meaning of the QOS level that is decided when a message is published: 0 when we prefer that the message will not arrive at all rather than arrive twice 1 when we want the message to arrive at least…
Oren
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Pika + RabbitMQ: setting basic_qos to prefetch=1 still appears to consume all messages in the queue

I've got a python worker client that spins up a 10 workers which each hook onto a RabbitMQ queue. A bit like this: #!/usr/bin/python worker_count=10 def mqworker(queue, configurer): connection =…
growse
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What is the use/purpose of MQTT QoS?

I am studying the MQTT protocol and it seems that there is a contradiction in the very first lines of the specs: The protocol runs over TCP/IP, or over other network protocols that provide ordered, lossless, bi-directional connections. Its…
Pedro Affonso
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Is it possible to call device layer code from driver code in Linux Kernel

I am going through Linux Networking device driver code and wanted to know is it possible call device layer code from driver code. --- a/drivers/net/ethernet/realtek/8139too.c +++ b/drivers/net/ethernet/realtek/8139too.c @@ -1706,10 +1706,20 @@…
Amit Singh Tomar
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How to set the maximum TCP Maximum Segment Size on Linux?

In Linux, how do you set the maximum segment size that is allowed on a TCP connection? I need to set this for an application I did not write (so I cannot use setsockopt to do it). I need to set this ABOVE the mtu in the network stack. I have two…
Eric
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Windows Permissions/Policy required to use qWAVE

I'm attempting to use qWAVE (on Windows Server 2008 R2) to set arbitrary DSCP values on socket traffic. I think I'm setting up the flow correctly, but when I try to call QOSSetFlow(), I'm getting an ERROR_ACCESS_DENIED error ("The calling…
Chris Heilman
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How to setup Quality of Service?

I'm talking about http://en.wikipedia.org/wiki/Quality_of_service. With streaming stackoverflow podcasts and downloading the lastest updates to ubuntu, I would like to have QoS working so I can use stackoverflow without my http connections timing…
grom
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Are sockets reliable?

Is it a good idea to use sockets to send data between two servers, or should I use something like MQ for moving data. My questions: are sockets reliable, if I need once only/assured delivery of the data? Are there any other solutions? Thanks.
not-exactly-a-unixhater
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What's the difference between Priority Class and QoS in Kubernetes?

In Kubernetes we can set the priority of a pod to Guaranteed, Burstable or Best-Effort base on requests and limits. Another method to assign priorities in Kubernetes is to define a priorityClass object and assign a priorityClassName to a pod. How…
Mohammad Yosefpor
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How can I embed NetLimiter in my application

I have a C# client application that connects to multiple servers. I noticed that it is necessary to use NetLimiter activated rules in order to make my client connect correctly with higher priority when there is so many traffic on the client…
Matin Lotfaliee
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Why am I receiving 67 code from QOSStartTrackingClient method?

I am receiving error code 67 from the code below, which means ERROR_BAD_NET_NAME. Why is it happening? How can I fix it? SOCKADDR address; strcpy_s(address.sa_data, "8.8.8.8"); address.sa_family = AF_INET; if (!QOSStartTrackingClient(QoSHandle,…
Matin Lotfaliee
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How te retrieve stream statistics in Gstreamer?

First of all I would like to start by saying that I'm really new to Gstreamer and its capabilities so pardon my ignorance if my understanding or implementation was wrong, I am still learning . I would like to build a small streaming application in…
Andi Domi
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Can't set QOS markings on Mac OS Majave with the IP_TOS socket option using setsockopt

"Type of service" is defined as the second byte in the IPv4 header. Trying to set this byte in our outbound UDP traffic on our Mac OS app. Every example I have seen so far uses setsockopt for this int tos = 0x60; unsigned int…
Zach Hall
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How do I detect a mqtt message delivery failure sent with QoS 2?

I'm trying to implement a JAVA application, with the aim to publish into a specific MQTT topic. The message should be delivered with QoS 2 (delivered exactly once). But I seem to forget anything in my implementation (code of a JUnit implementation…
justus
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