ring-buffer | Ring buffer for inter-process communication | Socket library

This article describes using mmap to configure two virtual memory ranges to the same underlying buffer to avoid memory copies for managing circular buffers.

Can esp32 hardware support this? I’d like to use an i2c dma technique to read microphone audio data directly into a circular buffer and hand off windowed ranges of that buffer to tensorflow for analysis all on an esp32 without any avoidable memory copies.

This reddit thread discusses it, but I don’t know enough to interpret the answer. Can those api calls map to memory? Is there an alternative mechanism to achieve my efficiency goals?

I already went through many links like @RefreshScope and /refresh not working and Spring Boot 2: Refresh properties on the fly not working, but still things are not working for me.

I've developed spring-cloud-config-server

when I hit

POST ==> http://localhost:8002/actuator/refresh

I get the response

[ "config.client.version" ]

It looks like its somehow not loading the changed properties

pom.xml:

I have implemented a producer/consumer pattern using Qt threads. Multiple producer threads generate data that are combined by a consumer. Communication is implemented using signals/slots and queued connections. This works fine as long as the consumer is able to consume the data faster than the producer threads produce the data.

It is hard to make my code scale. Particularly it is easy to increase the number of producers but it is very hard to spawn more than one consumer thread.

Now the problem starts when running the software on a CPU/system that has a lot of cores. In that case I use more threads to produce data. It can sometimes happen (depending from the complexity of data generation) that the consumer is not able to handle the produced data in time. Then the Qt event queue fills rapidly with events and the memory consumption grows extremely.

I can solve this by using blocking queued connections. However this does not allow full CPU load since producers tend to wait unnecessarily for the consumer after each data emission.

In a non-Qt software I would use a queue/mailbox/ring-buffer with a fixed size that makes the producers sleep until the consumer frees space in that container. This mechanism limits memory consumption and allows best possible CPU load.

However I could not find an equivalent solution using Qt classes. The event queue is global and has no size property. Is there a Qt way to solve this optimally? If not, are there STL classes I can use to couple (Q)Threads in my way?

I very new concepts of audio processing and have a basic knowledge of C++, my end goal is to create a means to measure harmonic distortion on line-in audio; my thoughts are to write audio-in stream to a circular buffer, then read from the circular buffer to an FFT function; from the FFT data I can workout audio distortion.

So far I'm using Portaudio to write streamed audio to the circular buffer from it's streaming input callback; I've created a Thread that checks if there's any data in the circular buffer, if there is data, read it into a temporary buffer. As a means of a simple test, I'm merely echo'ing the number of elements to read from the circular buffer, this works but after a second or so, produces an incorrect value for 'read elements available' (18446744073709542400) followed by a Segmentation error; sample output and my code below:

I am reading driver code from Intel E1000E AND Realtek r1869 driver. I hvae the devices for both,

Currently I am studying ethtool_ops. I know Ethtool can be a tool for

Long story short, ethtool is a means to display and adjust generic NIC/driver parameters
(identification, the number of receive and transmit queues, receive and transmit offloads, you > name it) in a userspace application

But if you look at the struct ethtool_ops not everythhing is crystal clear

Below is a Ethtool struct

I created an overlapped WriteFile scheme, where one thread fills a ring-buffer and advances the head-pointer and calls WriteFile, and another thread watches events from OVERLAPPED writes to advance the tail pointer. The logic is behaving as expected, but the file size is not increasing, it remains the same and just over-writes from position 0. I tested this by writing incremental value into the memory written to the file, and the index data increases, but it keeps writing at what is effectively fseek(0).

Here is the code.

First I open the file as GENERIC_WRITE and FILE_FLAG_OVERLAPPED, and I create 8 events, one for each page I am going to write. Each page is 256KBytes. I was originally using just one event, but I wanted to verify that the # of events wasn't the problem.

I develop a Kivy Python application. It should have a sound effect. In Kivy it is simple as: