Started from interest, guided by profession.
Querying 1,000,000 times with 1,000,000 elements:
| Container | Mean(ms) | Min(ms) | Max(ms) | Range | AllocatedBytes | Operations | Ratio of Mean(ms) |
|---|---|---|---|---|---|---|---|
| Dictionary | 34.72 | 30.65 | 36.33 | 16% | 170 | 656 | 1.00x |
| ConcurrentDictionary | 129.94 | 128.51 | 131.43 | 2% | 542 | 60 | 3.74x |
| ConditionalWeakTable | 168.45 | 150.94 | 184.17 | 20% | 542 | 236 | 4.85x |
Consider a part of CSharp code as follows, and try to guess what is the value of instance.Number:
var instance = new SampleClass()
{
Number = 3;
};
Console.WriteLine(instance.Number); // What's the value of property 'Number'?
class SampleClass
{
public int Number {get; set;} = 1;
public SampleClass()
{
Number = 2;
}
}
This is a delegate with ref keyword on one of its parameters:
public delegate void FooByRef(ref int number);
This article is excerpted from an internal report for 'trustworthy AI systems for robots'.
The era of ROS1/2 is coming to an end. They were at vital importance back to the age when we needed to efficiently glue different modules and sensors together, therefore we could stand all of its drawbacks such as intrinsic performance issues and lack of structural design. However, the situation of robotics research has changed since the renaissance of neural-network-based technologies.
Usually there will be containers and images which are no longer in use, yet their creators just forgot to remove them, left them to remain in servers as 'Status: Exited, Last Used: 3 Years Ago'. Unused containers will hold up their images, and every image of those no longer used old versions will hold up 3~5GB disk space.
In this blog, I'll post some of my own reflections on software development or robotic software engineering to the Posts folder, and notes on what I've learned to the Notes folder.