Criticism of Linux rise in prominence of operating system-level virtualization using Linux has raised the profile of attacks against the kernel, and that Linus Torvalds is reticent to add mitigations against kernel-level attacks in official releases. Linux 4.12, released in 2017, enabled KASLR by default, but its effectiveness is debated. Con Kolivas, a former kernel developer, tried to optimize the kernel scheduler for interactive desktop use. He finally dropped the support for his patches due to the lack of appreciation for his development. In the 2007 interview "Why I quit: kernel developer Con Kolivas" he stated: At LinuxCon 2009, Linux creator Linus Torvalds
FLEX (operating system) increased disk reliability at the expense of compatibility and speed. Later, TSC introduced the multitasking, multi-user, Unix-like UniFLEX operating system, which required DMA disk controllers, 8" disk, and so sold in only small numbers. Several of the TSC computer languages were ported to UniFLEX. During the early 1980s, FLEX was offered by Compusense Ltd as an operating system for the 6809-based Dragon 64 home computer. FLEX (operating system) The FLEX single-tasking operating system was developed by Technical Systems Consultants (TSC) of West Lafayette, Indiana, for the Motorola 6800 in 1976. The original version was for 8" floppy disks and the