Jens Axboe
Encyclopedia
Jens Axboe is a Linux kernel
hacker. He is the current Linux kernel maintainer of the block layer and other block devices, along with contributing the CFQ
I/O scheduler
, Noop scheduler
, Deadline scheduler
and splice (system call)
IO architecture. Jens is also the author of the blktrace utility and kernel parts, which provides a way to trace every block IO activity in the Linux kernel. blktrace exists in 2.6.17 and later Linux kernels.
To facilitate his block layer work in the Linux kernel Jens created the Flexible IO tester (FIO) benchmarking and workload simulation tool. FIO is able to simulate various types of I/O loads, such as synchronous, asynchronous, mmap, etc., as well as specifying the number of threads or processes, read vs. write mix, and various other parameters. FIO was used to set the world record in April 2009 for the highest number of I/Os-per-second (IOPS)
in a single system.
Linux kernel
The Linux kernel is an operating system kernel used by the Linux family of Unix-like operating systems. It is one of the most prominent examples of free and open source software....
hacker. He is the current Linux kernel maintainer of the block layer and other block devices, along with contributing the CFQ
CFQ
Completely Fair Queuing is an I/O scheduler for the Linux kernel which was written in 2003 by Jens Axboe.-Description:CFQ places synchronous requests submitted by processes into a number of per-process queues and then allocates timeslices for each of the queues to access the disk...
I/O scheduler
I/O scheduling
Input/output scheduling is a term used to describe the method computer operating systems decide the order that block I/O operations will be submitted to storage volumes...
, Noop scheduler
Noop scheduler
The NOOP scheduler is the simplest I/O scheduler for the Linux kernel. This scheduler was developed by Jens Axboe.- Overview :The NOOP scheduler inserts all incoming I/O requests into a simple FIFO queue and implements request merging....
, Deadline scheduler
Deadline scheduler
Deadline scheduler is an I/O scheduler for the Linux kernel which was written in 2002 by Jens Axboe.- Overview :The goal of the Deadline scheduler is to guarantee a start service time for a request. It does that by imposing a deadline on all I/O operations to prevent starvation of requests. It also...
and splice (system call)
Splice (system call)
splice is a Linux-specific system call that moves data between a file descriptor and a pipe without a round trip to user space. The related system call vmsplice moves or copies data between a pipe and user space. Ideally, splice and vmsplice work by remapping pages and do not actually copy any...
IO architecture. Jens is also the author of the blktrace utility and kernel parts, which provides a way to trace every block IO activity in the Linux kernel. blktrace exists in 2.6.17 and later Linux kernels.
To facilitate his block layer work in the Linux kernel Jens created the Flexible IO tester (FIO) benchmarking and workload simulation tool. FIO is able to simulate various types of I/O loads, such as synchronous, asynchronous, mmap, etc., as well as specifying the number of threads or processes, read vs. write mix, and various other parameters. FIO was used to set the world record in April 2009 for the highest number of I/Os-per-second (IOPS)
IOPS
IOPS is a common performance measurement used to benchmark computer storage devices like hard disk drives , solid state drives , and storage area networks...
in a single system.
See also
- CFQ talk, at linux.org.au (with video), 2007