Comments for Hot About Linux http://www.hotaboutlinux.com For Those Who Like to Dig Deeper Thu, 02 Sep 2010 19:42:32 +0000 hourly 1 http://wordpress.org/?v=3.0.1 Comment on Tuning the Linux Kernel’s Completely Fair Scheduler by Bill Anderson http://www.hotaboutlinux.com/2010/01/tuning-the-linux-kernels-completely-fair-scheduler/comment-page-1/#comment-1502 Bill Anderson Thu, 02 Sep 2010 19:42:32 +0000 http://www.hotaboutlinux.com/?p=30#comment-1502 You can find the instructions in the Documentation/scheduler/sched-design-CFS.txt file in the Linux source tree. You can find the instructions in the Documentation/scheduler/sched-design-CFS.txt file in the Linux source tree.

]]> Comment on Tuning the Linux Kernel’s Completely Fair Scheduler by Bill Anderson http://www.hotaboutlinux.com/2010/01/tuning-the-linux-kernels-completely-fair-scheduler/comment-page-1/#comment-1501 Bill Anderson Thu, 02 Sep 2010 19:32:18 +0000 http://www.hotaboutlinux.com/?p=30#comment-1501 I checked the source for 2.6.32-24 and that CONFIG_KERNEL_DEBUG is now CONFIG_DEBUG_KERNEL and CONFIG_SCHED_DEBUG still does exist. Name changes between version is not uncommon. It makes working with the kernel more exciting. I checked the source for 2.6.32-24 and that CONFIG_KERNEL_DEBUG is now CONFIG_DEBUG_KERNEL and CONFIG_SCHED_DEBUG still does exist. Name changes between version is not uncommon. It makes working with the kernel more exciting.

]]> Comment on Tuning the Linux Kernel’s Completely Fair Scheduler by anonyomus http://www.hotaboutlinux.com/2010/01/tuning-the-linux-kernels-completely-fair-scheduler/comment-page-1/#comment-1500 anonyomus Wed, 18 Aug 2010 13:34:56 +0000 http://www.hotaboutlinux.com/?p=30#comment-1500 Does anyone know how to create the directory /dev/cpuctl and set a certain process to be scheduled in such a way. My interest is decreasing the performance of the kvm processe on my notebook that runs the Windows XP guest. It eats far too much CPU especially when it is used only Lotus Notes. Does anyone know how to create the directory /dev/cpuctl and set a certain process to be scheduled in such a way. My interest is decreasing the performance of the kvm processe on my notebook that runs the Windows XP guest. It eats far too much CPU especially when it is used only Lotus Notes.

]]> Comment on Tuning the Linux Kernel’s Completely Fair Scheduler by anonyomus http://www.hotaboutlinux.com/2010/01/tuning-the-linux-kernels-completely-fair-scheduler/comment-page-1/#comment-1499 anonyomus Wed, 18 Aug 2010 13:28:04 +0000 http://www.hotaboutlinux.com/?p=30#comment-1499 but the second portion of your post does work for Ubuntu 10.04 /boot/config-2.6.32-22-generic: # fgrep CONFIG_PREEMPT /boot/config-$(uname -r) CONFIG_PREEMPT_NOTIFIERS=y # CONFIG_PREEMPT_NONE is not set CONFIG_PREEMPT_VOLUNTARY=y # CONFIG_PREEMPT is not set but the second portion of your post does work for Ubuntu 10.04 /boot/config-2.6.32-22-generic:
# fgrep CONFIG_PREEMPT /boot/config-$(uname -r)
CONFIG_PREEMPT_NOTIFIERS=y
# CONFIG_PREEMPT_NONE is not set
CONFIG_PREEMPT_VOLUNTARY=y
# CONFIG_PREEMPT is not set

]]> Comment on Tuning the Linux Kernel’s Completely Fair Scheduler by anonyomus http://www.hotaboutlinux.com/2010/01/tuning-the-linux-kernels-completely-fair-scheduler/comment-page-1/#comment-1498 anonyomus Wed, 18 Aug 2010 13:26:26 +0000 http://www.hotaboutlinux.com/?p=30#comment-1498 fgrep CONFIG_KERNEL_DEBUG /boot/config-$(uname -r) Works in Ubuntu but won't return anything because the string is unusued. fgrep CONFIG_SCHED_DEBUG /boot/config_$(uname -r) Certainly won't work in Ubuntu fgrep CONFIG_KERNEL_DEBUG /boot/config-$(uname -r)
Works in Ubuntu but won’t return anything because the string is unusued.
fgrep CONFIG_SCHED_DEBUG /boot/config_$(uname -r)
Certainly won’t work in Ubuntu

]]> Comment on Trapped in Bourne Shell by Dean http://www.hotaboutlinux.com/2009/02/trapped-in-bourne-shell/comment-page-1/#comment-1495 Dean Tue, 06 Jul 2010 03:32:31 +0000 http://www.hotaboutlinux.com/?p=7#comment-1495 This article is full of fallacies. It is confounding Bourne shell syntax (on which the modern POSIX shell dash is based) with implementation issues in the SVR4 shell. Using [ instead of [[ isn't a sin; [ is a builtin on dash too: it doesn't fork so the "compelling reason" in the article is moot. dash is faster than bash, so the argument about shell syntax versus builtins is redundant: if you wanted speed, you wouldn't use bash in the first place (look up BUGS in the bash manpage, bash is "too big and too slow"). The sentence about #!/bin/sh "still invoking bash" under busybox is either wrong or very poorly-worded. The Bourne shell syntax has been standardised in POSIX, portability is a good enough reason for making shell scripts POSIX-compatible. If lazy people stopped using bashisms then more linux distributions could follow Ubuntu and Debian's lead and have /bin/sh point to dash by default, making things faster for everybody. This article is full of fallacies. It is confounding Bourne shell syntax (on which the modern POSIX shell dash is based) with implementation issues in the SVR4 shell. Using [ instead of [[ isn’t a sin; [ is a builtin on dash too: it doesn’t fork so the “compelling reason” in the article is moot. dash is faster than bash, so the argument about shell syntax versus builtins is redundant: if you wanted speed, you wouldn’t use bash in the first place (look up BUGS in the bash manpage, bash is “too big and too slow”).

The sentence about #!/bin/sh “still invoking bash” under busybox is either wrong or very poorly-worded.

The Bourne shell syntax has been standardised in POSIX, portability is a good enough reason for making shell scripts POSIX-compatible. If lazy people stopped using bashisms then more linux distributions could follow Ubuntu and Debian’s lead and have /bin/sh point to dash by default, making things faster for everybody.

]]> Comment on Installing Linux Kernel Source by Peter Krikels http://www.hotaboutlinux.com/2010/02/installing-linux-kernel-source/comment-page-1/#comment-1494 Peter Krikels Fri, 25 Jun 2010 11:38:10 +0000 http://www.hotaboutlinux.com/?p=50#comment-1494 cool :-) cool :-)

]]> Comment on KornShell’s Bad Rap by Bill Anderson http://www.hotaboutlinux.com/2009/01/kornshells-bad-rap/comment-page-1/#comment-1493 Bill Anderson Sun, 20 Jun 2010 14:36:26 +0000 http://www.hotaboutlinux.com/?p=3#comment-1493 I disagree. Had AT&T Research Labs not kept ksh93 as part of AST, the status of ksh today might be totally different. By the time ksh was released as open source, Bash had already established its dominant role. Alas, the UNIX distributions are still using ksh88. I disagree. Had AT&T Research Labs not kept ksh93 as part of AST, the status of ksh today might be totally different. By the time ksh was released as open source, Bash had already established its dominant role. Alas, the UNIX distributions are still using ksh88.

]]> Comment on KornShell’s Bad Rap by Manish Jain http://www.hotaboutlinux.com/2009/01/kornshells-bad-rap/comment-page-1/#comment-1492 Manish Jain Mon, 14 Jun 2010 08:24:54 +0000 http://www.hotaboutlinux.com/?p=3#comment-1492 The reason for Korn shell's unpopularity lies not in history, but in the present where it is far inferior in terms of user-friendliness and features as an interactive shell. Citing POSIX compliance for ksh's bad reputation is just creating an excuse for - what more properly are - its fundamental weaknesses. If Bash could have become a pleasure to work with by the late 90's, Korn shell could have at least tried being such a pain even in 2010. The reason for Korn shell’s unpopularity lies not in history, but in the present where it is far inferior in terms of user-friendliness and features as an interactive shell. Citing POSIX compliance for ksh’s bad reputation is just creating an excuse for – what more properly are – its fundamental weaknesses. If Bash could have become a pleasure to work with by the late 90′s, Korn shell could have at least tried being such a pain even in 2010.

]]> Comment on Installing Linux Kernel Source by Bill Anderson http://www.hotaboutlinux.com/2010/02/installing-linux-kernel-source/comment-page-1/#comment-1491 Bill Anderson Fri, 23 Apr 2010 21:27:31 +0000 http://www.hotaboutlinux.com/?p=50#comment-1491 This in not a command-line. The list shows you the lines that must be in the /etc/apt/sources file. This in not a command-line. The list shows you the lines that must be in the /etc/apt/sources file.

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