# incubator-crail

**Repository Path**: jmt1995/incubator-crail

## Basic Information

- **Project Name**: incubator-crail
- **Description**: Mirror of Apache crail (Incubating)
- **Primary Language**: Java
- **License**: Apache-2.0
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2021-03-29
- **Last Updated**: 2025-12-05

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

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![license](https://img.shields.io/github/license/apache/incubator-crail.svg)
[![Documentation Status](https://readthedocs.org/projects/incubator-crail/badge/?version=latest)](https://incubator-crail.readthedocs.io/en/latest/?badge=latest)

# Apache Crail (incubating)

Apache Crail is a fast multi-tiered distributed storage system designed from ground up for high-performance network and storage hardware.
It marks the backbone of the Crail I/O architecture, which is described in more detail on [crail.incubator.apache.org](http://crail.incubator.apache.org). 
The unique features of Crail include:

* Zero-copy network access from userspace
* Integration of multiple storage tiers such DRAM, flash and disaggregated shared storage
* Ultra-low latencies for both meta data and data operations. For instance: opening, reading and closing a small file residing in the distributed DRAM tier less than 10 microseconds, which is in the same ballpark as some of the fastest RDMA-based key/value stores
* High-performance sequential read/write operations: For instance: read operations on large files residing in the distributed DRAM tier are typically limited only by the performance of the network
* Very low CPU consumption: a single core sharing both application and file system client can drive sequential read/write operations at the speed of up to 100Gbps and more
* Asynchronous API leveraging the asynchronous nature of RDMA-based networking hardware
* Extensible plugin architecture: new storage tiers tailored to specific hardware can be added easily

Crail is implemented in Java offering a Java API which integrates directly with the Java off-heap memory. Crail is designed for performance critical temporary data within a scope of a rack or two.

## Documentation

For information about how to deploy, run, test and program against Crail:
* Refer to https://incubator-crail.readthedocs.org
* Or build from source by running `make html` in `/doc` and opening `/doc/build/html/index.html`


## Community

Please join the Crail developer mailing list for discussions and notifications. The list is at:

dev@crail.incubator.apache.org.

## Disclaimer

Apache Crail is an effort undergoing incubation at The Apache Software Foundation (ASF), sponsored by the Apache Incubator PMC.
Incubation is required of all newly accepted projects until a further review indicates that the infrastructure, communications,
and decision making process have stabilized in a manner consistent with other successful ASF projects.
While incubation status is not necessarily a reflection of the completeness or stability of the code,
it does indicate that the project has yet to be fully endorsed by the ASF.