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  What is goroutine?

Casual Talk Golang is quite enjoyable to write, aside from the tedious if err != nil checks. One of the fundamental reasons for the joy is goroutine, a core feature of Golang. Understanding goroutines in detail is worthwhile, as they contribute significantly to the pleasure of working with Golang. So, let's talk about goroutines, hoping to provide some insights to the readers. TL;DR: We'll start by talking about assembling a computer, then delve into some concepts of the operating system, such ...

   EXPLANATION,GOLANG,GOROUTINE     2024-01-21 03:26:10

  Origin of Windows blue screen

Many of you from old ages might see the classical blue Windows blue screen before.Do you still remember the most famous Windows blue screen incident during a presentation of a Windows 98 beta by Bill Gates at COMDEX on April 20 1998. But do you know the history of blue screen? John Vert, an ex-Windoes NT kernel guy, shared the story on Quora.  Back in 1991 John Vert wrote the original code for Windows NT 3.1 that put the video screen back into text mode and the routines to put text on it (a...

   Windows blue screen,History     2013-07-24 09:25:16

  Google open sources Leak Finder for JavaScript

Google recently open sourced a tools for finding memory leaks in JavaScript programs. In JavaScript you cannot have "memory leaks" in the traditional sense, but you can have objects which are unintentionally kept alive and which in turn keep alive other objects, e.g., large parts of DOM. Leak Finder for JavaScript works against the Developer tools remote inspecting protocol of Chrome, retrieves heap snapshots, and detects objects which are "memory leaks" according to a given leak definition. The...

   Google,Open source,JavaScript     2012-08-15 13:45:34

  C programming tips in SPARC architecture

If you are a newbie of C programmers in SPARC architecture (For example, working on Solaris), you should pay attention to the following tips:(1) By default, SPARC is big-endian (For Endianness, you can refer http://en.wikipedia.org/wiki/Endianness). It means for an integer (short, int, long, etc), the MSB will be stored in the lower address, while the LSB will be stored in the higher address. (2) SPARC requires byte-alignment. It means for a short (2 bytes long) variable, the star...

   C     2014-06-01 03:56:30

  The latest on Java-on-Java: the Oracle experiment that is gaining momentum

What is Project Metropolis? The not so hush-hush Project Metropolis is all set to implement Java on itself – popularly known in the developer community as Java-on-Java. Oracle has released updates on its progress, and they are very encouraging. The project will focus on building a JIT (just in time) compiler that is written in Java. It is being touted as the experimental clone of JDK (Java Development Kit) 10.  Work on ‘ahead of time’ compiling and Graal compiler is also i...

   HIRE JAVA DEVELOPERS     2017-05-22 08:49:32

  Use DTrace to diagnose gdb issues

A few days ago, I installed the newest 64-bit gdb program (version 7.7.1) on Solaris 10 (X86_64 platform) to debug programs. After playing with the gdb a day, I found 2 issues about gdb:(1) The "set follow-fork-mode child" command doesn't take effect. By default, after the parent process forks the child process, the gdb will track the parent process, so this command can make gdb begin to follow the child process. But this command works OK on Linux.(2) The gdb can't parse the 32-bit application c...

   DTrace, debug, gdb, UNIX     2014-06-28 05:11:20

  How to do pprof for gRPC service

gRPC is a RPC framework based on HTTP and is frequently used for communications among micro service inside the same organization network. However,  the service functions cannot be accessed via normal HTTP URL as it's not a WEB framework. In this case, how to do pprof on a gRPC service? The trick is starting a HTTP server asynchronously while starting the gRPC service. This HTTP server can be accessed to run prrof debug. go func(){ http.ListenAndServe(":10001", nil) }() Since it uses the de...

   GOLANG,PPROF,GRPC     2021-01-29 23:11:33

  Use Java ThreadLocal with caution

According to Oracle documentation, ThreadLocal is a class provides thread-local variables. These variables differ from their normal counterparts in that each thread that accesses one (via its get or set method) has its own, independently initialized copy of the variable. ThreadLocal instances are typically private static fields in classes that wish to associate state with a thread. In short, ThreadLocal variables are variables belong to a thread, not a class or an instance of a class. One common...

   JAVA,MEMORY LEAK, THREADLOCAL     2015-11-03 07:31:57

  Tricks with Direct Memory Access in Java

Java was initially designed as a safe managed environment. Nevertheless, Java HotSpot VM contains a “backdoor” that provides a number of low-level operations to manipulate memory and threads directly. This backdoor – sun.misc.Unsafe â€“ is widely used by JDK itself in packages like java.nio or java.util.concurrent. It is hard to imagine a Java developer that uses this backdoor in any regular development because this API is extremely dangerous...

   Java,Directly memory access,Tricks,JVM     2012-02-13 05:31:19

  What are some lesser known but useful Unix commands?

A few that come to mind, some less known, some more: xargs or parallel: run things in parallel, with lots of options sed and awk: more well-known but still super useful for processing text files, and faster than Python or Ruby m4: simple macro processor screen: powerful terminal multiplexing and session persistence yes: print a string a lot cal: nice calendar env: run a command (useful in scripts) look: find English words (or lines in a file) beginning with a string cut and paste and join: data...

   Linux,Unix,Command,Less used     2011-12-27 09:27:49

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