Kernel - Revision history

Iskra: /* Log files, etc */

2009-05-08T19:58:07Z

Log files, etc

Iskra at 19:57, 8 May 2009

2009-05-08T19:57:52Z

Iskra at 19:44, 8 May 2009

2009-05-08T19:44:31Z

Iskra at 17:58, 8 May 2009

2009-05-08T17:58:37Z

Iskra at 17:00, 8 May 2009

2009-05-08T17:00:50Z

Iskra: /* Kernel (command line) parameters */

2009-05-07T18:24:57Z

Kernel (command line) parameters

Iskra: /* Kernel (command line) arguments */

2009-05-06T20:45:35Z

Kernel (command line) arguments

Iskra at 20:31, 6 May 2009

2009-05-06T20:31:42Z

Show changes

Iskra at 20:04, 5 May 2009

2009-05-05T20:04:04Z

Kazutomo at 19:02, 30 April 2009

2009-04-30T19:02:28Z

@@ Line 183: / Line 183: @@
 The compute node and I/O node logfiles have been discussed extensively in [[Testing#Log files|Testing]].
-In addition to regular console logs, the kernels can also generate RAS messages, which will not appear in the log files; they are instead stored in a database on the service node. At Argonne we have a command line tool named <tt>bg-listevents</tt> that shows a record of RAS events (type <tt>bg-listevents -h</tt> for command line arguments).
+In addition to regular console logs, the kernels can also generate RAS messages, which will not appear in the log files; they are instead stored in a database on the service node. At Argonne we have a custom command line tool named <tt>bg-listevents</tt> that shows a record of RAS events (type <tt>bg-listevents -h</tt> for command line arguments).
 ----
 [[MPICH, DCMF, and SPI]] | [[ZeptoOS_Documentation|Top]] | [[Ramdisk]]

@@ Line 128: / Line 128: @@
 </pre>
-If options are omitted, the tool shows the current kernel parameters.
+If options are omitted, the tool shows the current kernel parameters:
 <pre>
-$ ./kernel/zkparam.py  BGP-CN-zImage-with-initrd.elf  zepto_console_output=2
+$ ./kernel/zkparam.py BGP-CN-zImage-with-initrd.elf zepto_console_output=2
-$ ./kernel/zkparam.py  BGP-CN-zImage-with-initrd.elf
+$ ./kernel/zkparam.py BGP-CN-zImage-with-initrd.elf
 Current Kernel Parameters:
   zepto_console_output=2
@@ Line 181: / Line 181: @@
 -->
-The compute node and I/O node logfile have been discussed extensively in [[Testing#Log files|Testing]].
+The compute node and I/O node logfiles have been discussed extensively in [[Testing#Log files|Testing]].
-In addition to regular console logs, the kernels can also generate RAS message, which will not appear in the log files. A command line tool named <tt>bg-listevents</tt> shows you a record of RAS events. Type <tt>bg-listevents -h</tt> for command line arguments.
+In addition to regular console logs, the kernels can also generate RAS messages, which will not appear in the log files; they are instead stored in a database on the service node. At Argonne we have a command line tool named <tt>bg-listevents</tt> that shows a record of RAS events (type <tt>bg-listevents -h</tt> for command line arguments).
 ----
 [[MPICH, DCMF, and SPI]] | [[ZeptoOS_Documentation|Top]] | [[Ramdisk]]

@@ Line 90: / Line 90: @@
 When one invokes <tt>make</tt> with a kernel build target for the first time, the associated kernel config file is copied to <tt>.config</tt> in the kernel build directory.  <tt>config/bgp-cn-2.6.19.2-dot-config</tt> is applied to the CN Linux kernel build tree, and <tt>config/bgp-ion-2.6.16.46-dot-config</tt> is applied to the ION Linux kernel build tree.
-Here is the location of the kernel config file:
+Here are the locations of the kernel config files:
 * Regular build
 ** work/build-2.6.19.2-BGP-V1R3/.config
@@ Line 98: / Line 98: @@
 ** repo/build-2.6.16.46-297-BGP-V1R3/.config
-Please note that the kernel config file is copied only once, until you do a <tt>distclean</tt> or remove the files manually.
+Please note that the kernel config file is copied only once, until one does a <tt>distclean</tt> or removes the files manually.
 The <tt>bgp-cn-linux-menuconfig</tt> and <tt>bgp-ion-linux-menuconfig</tt> <tt>make</tt> targets invoke text-based Linux kernel configuration menus:
@@ Line 113: / Line 113: @@
 </pre>
-These menu targets never update the default kernel config files from the <tt>config</tt> directory.  If you want to apply a new config permanently, please copy it to the <tt>config</tt> directory by hand:
+These menu targets never update the default kernel config files from the <tt>config</tt> directory.  If one wants to apply a new config permanently, please copy it to the <tt>config</tt> directory by hand:
 <pre>
-$ cp work/build-2.6.19.2-BGP-V1R3/.config  config/bgp-cn-2.6.19.2-dot-config
+$ cp work/build-2.6.19.2-BGP-V1R3/.config config/bgp-cn-2.6.19.2-dot-config
 </pre>
 ==Kernel (command line) parameters==
-In common server/desktop Linux environments, kernel parameters can be passed via bootloader such as grub. However, Blue Gene/P boot mechanism does not provide such capability, so we have modified the CN Linux kernel (2.6.19) to use a kernel parameter string embedded in kernel ELF image file itself.
+In common server/desktop Linux environments, kernel parameters can be passed via a bootloader such as grub. However, Blue Gene/P boot mechanism does not provide such capability, so we have modified the CN Linux kernel (2.6.19) to use a kernel parameter string embedded in kernel ELF image file itself.
-One can (re)set the kernel parameters in a kernel ELF file using a command line tool <tt>zkparam.py</tt>, located in the <tt>bin<tt> subdirectory of the ZeptoOS installation directory.  Here is the synopsis of the tool:
+One can (re)set the kernel parameters in a kernel ELF file using a command line tool <tt>zkparam.py</tt>, located in the <tt>bin</tt> subdirectory of the ZeptoOS installation directory.  Here is the synopsis of the tool:
 <pre>

@@ Line 37: / Line 37: @@
 The <tt>prebuilt</tt> directory contains prebuilt kernel images and modules. While a complete prebuilt ION kernel ELF file is provided, for the CN kernel we provide intermediate object files instead.  This is because we embed the CN ramdisk in the CN kernel image when building ZeptoOS, and this process requires the object files.
-The <tt>tarball</tt> directory contains kernel tarballs separately for the ION and the CN Linux kernel. Technically, those tarballs are a snapshot of the ZeptoOS kernel git repository. The directory might contain a <tt>.patch</tt> file that contains the differences between the last snapshot and the current git HEAD since we wanted to avoid creating a snapshot from git for small modifications. Associated git log file can also be found in this directory. A <tt>.SNAPSHOT_HEAD</tt> file indicates the git revision at the time when a snapshot was created, so this information is used to create a patch file.
+The <tt>tarball</tt> directory contains kernel tarballs separately for the ION and the CN Linux kernel. Technically, those tarballs are snapshots of the ZeptoOS kernel git repository. The directory might contain a <tt>.patch</tt> file that contains the differences between the last snapshot and the current git HEAD since we wanted to avoid creating a snapshot from git for small modifications. Associated git log files can also be found in this directory. A <tt>.SNAPSHOT_HEAD</tt> file indicates the git revision at the time when a snapshot was created, so this information is used to create a patch file.
-Here is a list of files for the CN kernel:
+As an example, here is a list of files for the CN kernel:
 <pre>
@@ Line 52: / Line 52: @@
 ==Building a kernel==
-<tt>Makefile</tt> in the <tt>kernel</tt> directory has many options. Just type <tt>make</tt> and it will print out a help message.
+The <tt>Makefile</tt> in the <tt>kernel</tt> directory has many targets. Just type <tt>make</tt> and it will print out a help message.
-If one needs to build (or rebuild) a kernel from the source tarball, use <tt>bgp-ion-linux-build</tt> or <tt>bgp-cn-linux-build</tt> target. By default, it extracts ION or CN kernel tarball in a directory named <tt>work</tt>, applies a patch if any and starts the kernel build. Once the kernel has successfully been built, kernel images (in both ZeptoOS top-level directory and the <tt>tmp</tt> directory) will be replaced with newly built images. The ION kernel source code is extracted into <tt>work/linux-2.6.16.46-297-BGP-V1R3</tt> and the CN kernel source into <tt>work/linux-2.6.19.2-BGP-V1R3</tt>.
+If one needs to build (or rebuild) a kernel from a source tarball, use <tt>bgp-ion-linux-build</tt> or <tt>bgp-cn-linux-build</tt> targets. By default, it extracts ION or CN kernel tarball in a directory named <tt>work</tt>, applies a patch if any and starts the kernel build. Once the kernel has successfully been built, kernel images (in both ZeptoOS top-level directory and the <tt>tmp</tt> directory) will be replaced with newly built ones. The ION kernel source code is extracted into <tt>work/linux-2.6.16.46-297-BGP-V1R3</tt> and the CN kernel source into <tt>work/linux-2.6.19.2-BGP-V1R3</tt>.
 Here is an example of building and rebuilding the CN kernel:
@@ Line 71: / Line 71: @@
 ===Building a kernel from the ZeptoOS kernel git repository===
-As mentioned earlier, the kernel tarball is used as the source by default.  If instead one passes <tt>GIT=1</tt> to <tt>make</tt>, one can build directly from the ZeptoOS kernel git tree. This is very useful for kernel development since it makes it easier to keep track of local modifications.
+As mentioned earlier, kernel tarballs are used as the source by default.  If instead one passes <tt>GIT=1</tt> to <tt>make</tt>, one can build directly from the ZeptoOS kernel git tree. This is very useful for kernel development since it makes it easier to keep track of local modifications.
 <pre>
@@ Line 82: / Line 82: @@
 </pre>
-This will create <tt>repo/linux-2.6.19.2-BGP-V1R3</tt>, which is a git repository that is cloned from http://git.anl-external.org/bg-linux.repos/linux-2.6.19-BGP-V1R3.git/. Our http repo is read-only, so you cannot push your modifications to it. Instead, please post any patches to the [mailto:zeptoos@lists.mcs.anl.gov ZeptoOS mailing list] instead.
+This will create <tt>repo/linux-2.6.19.2-BGP-V1R3</tt>, which is a git repository that is cloned from http://git.anl-external.org/bg-linux.repos/linux-2.6.19-BGP-V1R3.git/. Our http repo is read-only, so you cannot push your modifications to it. Instead, please post any patches to the [mailto:zeptoos@lists.mcs.anl.gov ZeptoOS developers mailing list].
 See also the [http://bg-linux.anl-external.org/wiki/index.php/Main_Page BG-Linux page] for the details on our kernel git repository.

@@ Line 4: / Line 4: @@
 ==Introduction==
-We currently provide two Linux kernels because of GPFS support on ION.
+We currently provide two Linux kernels:
 * 2.6.19-based kernel: ZeptoOS CN kernel
 ** IBM V1R3 patch and ZeptoOS patch applied
-** 64&nbsp;KB pagesize and big memory region available
+** 64&nbsp;KB page size and big memory region available
 ** Device drivers for compute node devices such as DMA, lockbox, etc
 ** Allows to run MPICH/DCMF code through Zepto Compute Binary (ZCB)
@@ Line 17: / Line 17: @@
 ** Only minor changes compared to the IBM ION kernel.
-We focus our development efforts on the 2.6.19-based kernel.  It is meant primarily for the compute nodes, but can also be used on the I/O nodes.  The problem is that GPFS does not work with this kernel, so we also provide the 2.6.16-based kernel which works with GPFS.
+We focus our development efforts on the 2.6.19-based kernel.  It is meant primarily for the compute nodes, but can also be used on the I/O nodes.  The problem is that GPFS does not work with this kernel, so we also provide the 2.6.16-based kernel which GPFS does work with.
 ==Kernel directory structure==
-The <tt>kernel</tt> directory basically consists of three main subdirectories: <tt>prebuilt</tt>, <tt>config</tt>, and <tt>tarball</tt>.
+The <tt>kernel</tt> directory consists of three main subdirectories: <tt>prebuilt</tt>, <tt>config</tt>, and <tt>tarball</tt>.
 <pre>

@@ Line 118: / Line 118: @@
 </pre>
-==Kernel (command line) arguments==
+==Kernel (command line) parameters==
-In common server/desktop Linux environments, kernel parameters can be passed via bootloader such as grub. However, BlueGene/P boot mechanism does not have such capability. Kernel parameters are very handy, since we can skip kernel rebuild. So we have modified the CN Linux kernel (2.6.19) to allow to load kernel parameter string
+In common server/desktop Linux environments, kernel parameters can be passed via bootloader such as grub. However, Blue Gene/P boot mechanism does not provide such capability, so we have modified the CN Linux kernel (2.6.19) to use a kernel parameter string embedded in kernel ELF image file itself.
-You can add kernel parameters (or reset) to a kernel ELF file by
+You can (re)set the kernel parameters to a kernel ELF file by a command line tool named zkparam.py, which is located in kernel directory.  Here is the synopsis of the tool:
 <pre>
-zkparam.py  KERNEL_ELF  [options]
+zkparam.py <kernel_image> [options]
 </pre>
-If you omit options, the tool shows you the current kernel parameters.
+If you omit options, the tool shows the current kernel parameters.
 <pre>
@@ Line 140: / Line 137: @@
 </pre>
-===Zepto kernel specific kernel parameters===
+===ZeptoOS-pecific kernel parameters===
-* '''zepto_debug'''=INTEGER
+* '''zepto_debug'''=<integer>
-** Specify the zepto kernel debug level
+** Specifies the ZeptoOS kernel debug level.
-** 0 turns off all zepto debug msgs. higher number more detail
+** The higher the number, the more messages are generated.
 ** default=1
-* '''flatmemsizeMB'''=INTEGER
+* '''flatmemsizeMB'''=<integer>
-** Specify the size of flatmemory in MB.
+** Specifies the size of big memory in MB.
-** Currently the granularity of memory size is limited to 256 MB
+** Currently the granularity of memory size is 256&nbsp;MB.
 ** default=256  min=256  max=1792
-* '''zepto_console_output'''=INTEGER
+* '''zepto_console_output'''=<integer>
-** Specify the console output behavior.
+** Specifies the console output behavior.
-** 0 disables all console output from kernel.
+** 0 disables console output from all compute nodes.
-** 1 enables console output from one of nodes(personality rank=1)
+** 1 enables console output from the first compute node ([[FAQ#Torus rank|torus rank]] 0).
-** 2 enables console output from all nodes
+** 2 enables console output from all compute nodes.
 ==Log files, etc==

@@ Line 1: / Line 1: @@
 ==Introduction==
@@ Line 203: / Line 206: @@
 A command line tool named bg-listevents shows you a record of RAS events.
 Type 'bg-listevents -h' for command line parameters.

← Older revision		Revision as of 19:02, 30 April 2009
Line 1:		Line 1:
		+	==Introduction==
		+
	We currently provide two Linux kernels because of GPFS support on ION.		We currently provide two Linux kernels because of GPFS support on ION.