Con Kolivas is an Australian anaesthetist.Anaesthesia Information Page
by Kolivas, Jan 2001 He has worked as a

computer programmer A computer programmer, sometimes referred to as a software developer, a software engineer, a programmer or a coder, is a person who creates computer programs — often for larger computer software. A programmer is someone who writes/creates ...

on the

Linux kernel The Linux kernel is a free and open-source, monolithic, modular, multitasking, Unix-like operating system kernel. It was originally authored in 1991 by Linus Torvalds for his i386-based PC, and it was soon adopted as the kernel for the GNU ...

and on the development of the cryptographic currency mining software CGMiner.CGMiner GitHub repository, "ASIC and FPGA miner in c for bitcoin"
/ref> His Linux contributions include

patch Patch or Patches may refer to: Arts, entertainment and media * Patch Johnson, a fictional character from ''Days of Our Lives'' * Patch (''My Little Pony''), a toy * "Patches" (Dickey Lee song), 1962 * "Patches" (Chairmen of the Board song ...

es for the kernel to improve its desktop performance, particularly reducing I/O impact.

Linux

Kolivas is most notable for his work with CPU scheduling, most significantly his implementation of " fair scheduling", which inspired Ingo Molnár to develop his Completely Fair Scheduler, as a replacement for the earlier

O(1) scheduler An O(1) scheduler (pronounced "O of 1 scheduler", "Big O of 1 scheduler", or "constant time scheduler") is a kernel scheduling design that can schedule processes within a constant amount of time, regardless of how many processes are running on the ...

, crediting Kolivas in his announcement., 18 April 2007, ''KernelTrap.org'' Kolivas developed several CPU schedulers such as the Staircase in 2004, then Rotating Staircase Deadline (RSDL), and subsequently Staircase Deadline (SD) schedulers to address interactivity concerns of the Linux kernel with respect to desktop computing. Additionally, he has written a " swap prefetch" patch, which allows processes to respond quickly after the

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ef ...

has been idle for some time and their

working set Working set is a concept in computer science which defines the amount of memory that a process requires in a given time interval. Definition Peter Denning (1968) defines "the working set of information W(t, \tau) of a process at time t to be t ...

s have been swapped out. Many of his experimental "-CK" patches, such as his prefetching and scheduling code, did not get merged with the official Linux kernel. In 2007, Kolivas announced in an email that he would cease developing for the Linux kernel. Discussing his reasons in an interview, he expressed frustration with aspects of the mainline kernel development process, which he felt did not give sufficient priority to desktop interactivity, in addition to hacking taking a toll on his health, work and family. He has also written a benchmarking tool called ConTest that can be used to compare the performance of different kernel versions. On 31 August 2009, Kolivas posted a new scheduler called BFS (

Brain Fuck Scheduler The Brain Fuck Scheduler (BFS) is a process scheduler designed for the Linux kernel in August 2009 as an alternative to the Completely Fair Scheduler (CFS) and the O(1) scheduler. BFS was created by an experienced kernel programmer Con Koliva ...

). It is designed for desktop use and to be very simple (hence it may not scale well to machines with many CPU cores). Con Kolivas did not intend to get it merged into the mainline kernel.BFS FAQ
/ref> He has since retired BFS in favour of MuQSS, a rewritten implementation of the same concept.

CGMiner

On 13 July 2011, Kolivas introduced a new piece of software for "windows, linux, OSX and other" called CGMiner, which is used for mining

cryptocurrencies A cryptocurrency, crypto-currency, or crypto is a digital currency designed to work as a medium of exchange through a computer network that is not reliant on any central authority, such as a government or bank, to uphold or maintain it. It ...

such as

bitcoin Bitcoin (abbreviation: BTC; sign: ₿) is a decentralized digital currency that can be transferred on the peer-to-peer bitcoin network. Bitcoin transactions are verified by network nodes through cryptography and recorded in a public distr ...

and

Litecoin Litecoin (Abbreviation: LTC; sign: Ł) is a decentralized peer-to-peer cryptocurrency and open-source software project released under the MIT/X11 license. Inspired by Bitcoin, Litecoin was among the earliest altcoins, starting in October 201 ...

References

External links

Kolivas's personal website
{{DEFAULTSORT:Kolivas, Con Australian people of Greek descent Australian computer programmers Australian anaesthetists Linux kernel programmers Medical doctors from Melbourne Living people Year of birth missing (living people)