Maximum Clique Algorithm. C++ API - Protocol Buffers. Google::protobuf Core components of the Protocol Buffers runtime library. The files in this package represent the core of the Protocol Buffer system. All of them are part of the libprotobuf library. A note on thread-safety: Thread-safety in the Protocol Buffer library follows a simple rule: unless explicitly noted otherwise, it is always safe to use an object from multiple threads simultaneously as long as the object is declared const in all threads (or, it is only used in ways that would be allowed if it were declared const). However, if an object is accessed in one thread in a way that would not be allowed if it were const, then it is not safe to access that object in any other thread simultaneously.
Put simply, read-only access to an object can happen in multiple threads simultaneously, but write access can only happen in a single thread at a time. google::protobuf::io Auxiliary classes used for I/O. google::protobuf::compiler repeated_field.h Implementation of the Protocol Buffer compiler. Integrating C++ and Java. Using C++ code from within a Java application, and calling from C++ to a Java object SummaryThis article explores some of the issues involved in integrating C++ code into a Java program.
It shows how to call from a Java object to a C++ object, and how to call from a C++ object to a Java object. Issues such as interaction with garbage collection are explored, and a simple framework for integrating Java and C++ is developed. Finally, current solutions are compared with what can be expected with JDK 1.1, as well as future offerings. By Bill Foote In this article, I'll discuss some of the issues involved in integrating C++ code with a Java application. Why integrate C++ and Java? Why would you want to integrate C++ code into a Java program in the first place?
Performance. If you take the plunge and decide to integrate Java and C++, you give up some of the important advantages of a Java-only application, however. A mixed C++/Java application can not run as an applet.You give up pointer-safety. Documentation (Project fuse.Documentation. Fuse file info - fuse. Anatomy of the Linux file system. Basic file system architecture The Linux file system architecture is an interesting example of abstracting complexity. Using a common set of API functions, a large variety of file systems can be supported on a large variety of storage devices.
Take, for example, the read function call, which allows some number of bytes to be read from a given file descriptor. The read function is unaware of file system types, such as ext3 or NFS. Back to top What is a file system? I'll start with an answer to the most basic question, the definition of a file system. Mounting Associating a file system to a storage device in Linux is a process called mounting. To illustrate the capabilities of the Linux file system layer (and the use of mount), create a file system in a file within the current file system.
Listing 1. . $ dd if=/dev/zero of=file.img bs=1k count=10000 10000+0 records in 10000+0 records out $ You now have a file called file.img that's 10MB. . $ losetup /dev/loop0 file.img $ Listing 2. Listing 3. Les fichiers. Les fichiers Les fichiers Unix sont non typés et sont des simples séquences d'octets: d'autres systèmes ont des fichiers typés (fichier avec enregistrement de longueur fixe ou variable, fichier indexé, fichiers partitionnés, etc.). Un fichier est décrit par un inode qui pointe vers les données: (fichier /usr/include/sys/stat.h) struct stat { dev_t st_dev; ino_t st_ino; mode_t st_mode; short st_nlink; uid_t st_uid; gid_t st_gid; dev_t st_rdev; off_t st_size; time_t st_atime; time_t st_mtime; time_t st_ctime; long st_blksize; long st_blocks; }; Les champs st_dev : le device où est le fichier. Organisation des données Les données elles-mêmes sont accédées via des blocs indirects, double-indirects et triple-indirects.
Noms de fichiers et répertoires Un nom pointe sur un numéro d'inode. Extensions des droits: les ACL Autres droits imaginables: Windows read, write, read/execute, list, modify Posix append only, no dump, immutable, secure deletion (= fill 0), no atime updates, etc. 1 Reference Manual :: 21.4.5.5 MySQL Connector/C++ Complete Example 1. Writing a FUSE Filesystem: a Tutorial. Joseph J. Pfeiffer, Jr., Ph.D. Emeritus Professor Department of Computer Science New Mexico State Universitypfeiffer@cs.nmsu.edu Version of 2012-11-15 One of the real contributions of Unix has been the view that "everything is a file". A tremendous number of radically different sorts of objects, from data storage to file format conversions to internal operating system data structures, have been mapped to the file abstraction.
One of the more recent directions this view has taken has been Filesystems in User Space, or FUSE (no, the acronym really doesn't work. There are many documents on the web describing how FUSE works and how to install and use a FUSE filesystem, but I haven't come across any that try to describe how to go about actually writing one. This tutorial introduces FUSE using a filesystem I call the "Big Brother File System" (the reason for the name is that "Big Brother is watching. " I am not affiliated with the FUSE project in any way, except as a user. Organization License. Fuse. Avec FUSE, abréviation de Filesystem in Userspace1), il est possible d'implémenter toutes les fonctionnalités d'un système de fichier dans un espace utilisateur. Ces fonctionnalités incluent : une API de bibliothèque simple ; une installation simple (pas besoin de patcher ou recompiler le noyau) ; une implémentation sécurisée ; utilisable dans l'espace utilisateur.
Aujourd'hui, pour monter un système de fichier, il faut être administrateur ou que celui-ci l'ait prévu dans « /etc/fstab » avec des informations en dur. FUSE permet à un utilisateur de monter lui-même un système de fichier. Programmes utilisant FUSE Pour profiter de FUSE, il faut des programmes qui exploitent sa bibliothèque et ces programmes sont nombreux. Installation Rien de plus simple sur Ubuntu : Utilisation Il faut ajouter les utilisateurs pouvant utiliser FUSE dans le groupe fuse : $ sudo adduser $USER fuse Disponible dans les dépôt d'Ubuntu Exemple pour fuseiso : Non disponible dans les dépôts d'Ubuntu Utilisation de fusauto. Diagrams Online | draw.io. I-FAAST – File Optimization Technology | Diskeeper. I-FAAST (Intelligent File Access Acceleration Sequencing Technology), a proprietary innovative technology developed and patented by Condusiv Technologies, is the leading solution that uses real data about each individual disk's performance to make intelligent decisions to speed up file access.
Modern HDD drives have significant performance variances across their physical media. Third party tools can be used to benchmark the 2x and greater improvement that can be leveraged for read and write throughput, given that the most optimal disk areas are utilized for the most frequently accessed data. New developments in the I-FAAST technology has added the ability to intelligently and automatically assign the files being used to the right “media” (SSD or HDD) This is based on usage, how frequently and how recently the files have been used, and on the availability of the media itself. For further information regarding I-FAAST contact us at: OEM@condusiv.com. e4rat. e4rat (ext4 – reduced access time) est un outil permettant d’accélérer le démarrage de votre distribution Ubuntu en déplaçant certains fichiers de démarrage en début du disque dur réduisant considérablement le temps de démarrage. C'est donc une alternative à ureadahead utilisé par défaut par Ubuntu.
Attention, cet outil n'est pas officiellement supporté par Ubuntu et modifie en profondeur votre système: utilisez-le à vos risques et périls. Pour configurer e4rat, il vous faut redémarrer votre ordinateur et lorsque le menu de grub-pc apparaît, appuyez sur la touche “e” pour l'éditer. À la fin de la ligne kernel /vmlinuz26 root=/dev/disk/by-uuid/… ou de la ligne linux /boot/vmlinuz-… ajoutez ceci: init=/sbin/e4rat-collect et appuyez sur <Ctrl> + <X> pour lancer Ubuntu avec la nouvelle option. Une fois dans votre session et pendant 2 minutes, e4rat va collecter et enregistrer dans le fichier /var/lib/e4rat/startup.log tout ce que vous faites comme lancer Firefox, Thunderbird, … single. Protobuf - Protocol Buffers - Google's data interchange format. What is it? Protocol Buffers are a way of encoding structured data in an efficient yet extensible format.
Google uses Protocol Buffers for almost all of its internal RPC protocols and file formats. Latest Updates Documentation Read the documentation. Discussion Visit the discussion group. Quick Example You write a .proto file like this: message Person { required int32 id = 1; required string name = 2; optional string email = 3;} Then you compile it with protoc, the protocol buffer compiler, to produce code in C++, Java, or Python. Then, if you are using C++, you use that code like this: Person person;person.set_id(123);person.set_name("Bob");person.set_email("bob@example.com"); fstream out("person.pb", ios::out | ios::binary | ios::trunc);person.SerializeToOstream(&out);out.close(); Or like this: Person person;fstream in("person.pb", ios::in | ios::binary);if (! For a more complete example, see the tutorials.
FUSE: Filesystem in Userspace. Ureadahead. Ureadahead (Über-readahead) is used to speed up the boot process. It works by reading all the files required during boot and makes pack files for quicker access, then during boot reads these files in advance, thus minimizes the access times for the harddrives. It's intended to replace sreadahead. Requirements Ureadahead needs a kernel patch to work, which is no longer available on the AUR. The user-space package is called ureadahead. How it works When run without any arguments, ureadahead checks for pack files in /var/lib/ureadahead, and if none are found or if the packfiles are older than a month, it starts tracing the boot process.
Otherwise, if the file is up to date, it just reads the pack file in preparation for the boot. It works for both SSDs and traditional harddrives and automatically optimizes the pack files depending on which you have. Using ureadahead First you need the patched kernel. Ureadahead() { /sbin/ureadahead --timeout=240 & } add_hook sysinit_end ureadahead Configuration. Bootchart.