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layout: default
navsection: architecture
title: "Arvados components"
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Copyright (C) The Arvados Authors. All rights reserved.

SPDX-License-Identifier: CC-BY-SA-3.0
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h3. Services

Located in @arvados/services@ except for Workbench which is located in @arvados/apps/workbench@.

table(table table-bordered table-condensed).
|_. Component|_. Description|
|api|The API server is the core of Arvados.  It is backed by a Postgres database and manages information such as metadata for storage, a record of submitted compute jobs, users, groups, and associated permissions.|
|arv-git-httpd|Provides a git+http interface to Arvados-managed git repositories, with permissions and authentication based on an Arvados API token.|
|arvados-dispatch-cloud|Provide elastic computing by creating and destroying cloud based virtual machines on compute demand.|
|crunch-dispatch-local|Get compute requests submitted to the API server and execute them locally.|
|crunch-dispatch-slurm|Get compute requests submitted to the API server and submit them to slurm.|
|crunch-run|Dispatched by crunch-dispatch, executes a single compute run: setting up a Docker container, running it, and collecting the output.|
|dockercleaner|Daemon for cleaning up Docker containers and images.|
|fuse|Filesystem in USErspace (FUSE) filesystem driver for Keep.|
|health|Health check proxy, contacts configured Arvados services at their health check endpoints and reports results.|
|keep-balance|Perform storage utilization reporting, optimization and garbage collection.  Moves data blocks to their optimum location, ensures correct replication and storage class, and trashes unreferenced blocks.|
|keepproxy|Provides low-level access to keepstore services (block-level data access) for clients outside the internal (private) network.|
|keepstore|Provides access to underlying storage (filesystem or object storage such as Amazon S3 or Azure Blob) with Arvados permissions.|
|keep-web|Provides high-level WebDAV access to collections (file-level data access).|
|login-sync|Synchronize virtual machine users with Arvados users and permissions.|
|arvados-ws|Publishes API server change events over websockets.|
|workbench|Web application providing user interface to Arvados services.|

h3. Tools

The @arv@ command is located in @arvados/sdk/ruby@, the @arv-*@ tools are located in @arvados/sdk/python@, the rest are located in @arvados/tools@.

table(table table-bordered table-condensed).
|_. Component|_. Description |
|arv|Provides command line access to API, also provides some purpose utilities.|
|arv-copy|Copy a collection from one cluster to another|
|arv-get|Get files from a collection.|
|arv-keepdocker|Upload Docker images from local Docker daemon to Keep.|
|arv-ls|List files in a collection|
|arv-migrate-docker19|Migrate Docker images in Keep from v1 format (Docker 1.9 or earlier) to v2 format (Docker 1.10 or later)|
|arv-normalize|Read manifest text on stdin and produce normalized manifest text on stdout.|
|arv-put|Upload files to a collection.|
|arv-ws|Print events from Arvados websocket event source.|
|arvbash|Helpful @bash@ macros for using Arvados at the command line.|
|arvbox|Dockerized Arvados environment for development and testing.|
|crunchstat-summary|Read execution metrics (cpu %, ram, network, etc) collected from a compute container and produce a report.|
|keep-block-check|Given a list of keep block locators, check that each block exists on one of the configured keepstore servers and verify the block hash.|
|keep-exercise|Benchmarking tool to test throughput and reliability of keepstores under various usage patterns.|
|keep-rsync|Get lists of blocks from two clusters, copy blocks which exist on source cluster but are missing from destination cluster.|
|sync-groups|Take a CSV file listing with (group, user, permission) records and synchronize membership in Arvados groups.|