Public bug reported: When install Linux in SSD Drives ( EeePC, pendrive, etc ) or Virtual machines the default Linux I/O scheduler ( CFQ ) make disk access very slower, causing sometimes system/application freeze.
If the scheduler is changed to NOOP the access to disk have a big improvement : Kernel compilation CFQ : 4161 seconds NOOP: 3653 seconds ( 13% faster ) Link: http://www.alphatek.info/2009/02/02/ssd-performance-vs-linux- kernel-io-scheduler-in-fedora-10/ "The NOOP scheduler is a simple FIFO queue and uses the minimal amount of CPU/instructions per I/O to accomplish the basic merging and sorting functionality to complete the I/O. It assumes performance of the I/O has been or will be optimized at the block device (memory-disk) or with an intelligent HBA or externally attached controller." Link: http://www.redhat.com/magazine/008jun05/features/schedulers/ But, the most end-users don't know about this option/tunning and will very helpful automatic add "elevator=noop" to kernel initialization when ubiquity is installing Ubuntu in this devices. ** Affects: ubiquity (Ubuntu) Importance: Undecided Status: New ** Tags: feature request ** Description changed: When install Linux in SSD Drives ( EeePC, pendrive, etc ) or Virtual machines the default Linux I/O scheduler ( CFQ ) make disk access very slower, causing sometimes system/application freeze. If the scheduler is changed to NOOP the access to disk have a big improvement : Kernel compilation CFQ : 4161 seconds - NOOP: 3653 seconds ( 17% faster ) + NOOP: 3653 seconds ( 13% faster ) Link: http://www.alphatek.info/2009/02/02/ssd-performance-vs-linux- kernel-io-scheduler-in-fedora-10/ "The NOOP scheduler is a simple FIFO queue and uses the minimal amount of CPU/instructions per I/O to accomplish the basic merging and sorting functionality to complete the I/O. It assumes performance of the I/O has been or will be optimized at the block device (memory-disk) or with an intelligent HBA or externally attached controller." Link: http://www.redhat.com/magazine/008jun05/features/schedulers/ But, the most end-users don't know about this option/tunning and will very helpful automatic add "elevator=noop" to kernel initialization when ubiquity is installing Ubuntu in this devices. ** Tags added: feature request -- Change I/O scheduler to NOOP when installing in SSD Drive or virtual machines https://bugs.launchpad.net/bugs/390247 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
