LTC bulletin: February 28, 2002

Maya Stodte (mstodte@yahoo.com)
Technology journalist
February 2002

Our biweekly news in brief from the Linux Technology Center -- where all the Linux-related technologies inside IBM are tracked -- includes a new Li18nux release and LSB specification, as well as patches from the Linux Scalability Effort and Performance Co-Pilot. Samba also has a new release out.

The updates in this bulletin are arranged alphabetically by project. To find out more about any of these projects and others, visit the Linux Technology Center.

Linux Internationalization Initiative (Li18nux)
The Internationalization patch for GNU grep has been updated and committed in beta release. The changes were to grep commands to support multi-byte character sets and locale-sensitive behavior; the changes also fixed a bug of incorrect memory allocation, according to the patch maintainer, Isamu Hasegawa.

In other news from the Li18nux community, the Linux Internationalization Initiative released the new Li18nux 1.0 specification at LinuxWorld Expo in New York last month.

Li18nux is run by the Free Standards Group. It is working on developing internationalization specifications for Linux and related applications, and made a conformance test suite available in August of 2000. Many contributors from the LTC are working on patches to increase Linux conformance to these standards.

Journaled File System (JFS)
JFS has released version 1.0.14. The utilities changes fixed a typecast problem and removed some old types in order to clean up the code. The file system changes made two fixes, one to a hang in invalidate_metapages and one to anon_list. For more details and changes made in previous JFS releases, go to the changelog. This is the 52nd release of the JFS since its first beta release in December of 2000.

The Journaled File System technology from IBM, currently used in its enterprise servers, provides a log-based, byte-level file system designed for high-throughput server environments. Work is underway to complete the port to Linux.

Linux Scalability Effort
The Linux Scalability Effort has released several new patches, among them kernel development tools, userlevel locking, IO scalability patch, a read-copy update, APIC routing, and scalable CPU bitmasks. Detailed release notes for these patches are available through the project site on SourceForge.

The Linux Scalability Project is an investigation into Linux 2.4 SMP scalability, using Netbench® as a workload with Samba. The process scheduling and memory placement effort has made its design notes and more detailed information about the work on CpuMemSets available through the project site on SourceForge.

Linux Standard Base (LSB)
The Linux Standard Base specification 1.1 has been finalized. Appendix B was removed in the new specification because it was non-normative, and an FHS chapter was replaced. Among the new additions were curses, reentrant, and RPC interfaces; several interfaces were also removed due to lack of specification. For further details see the LSB 1.1 changelog.

The LSB is a family of specifications defining a binary system interface for compiled applications in order to insure a uniform industry-standard environment. The specification consists of a generic LSB and an architecture-specific LSB. The Linux Standard Base works to advance these standards among Linux distributions so that all Linux software can run on compliant systems. The LSB is also involved in development efforts and in recruiting vendors to the Linux platform.

Linux Test Project
The Linux Test Project (LTP) has released version 20020207. Among the new features added are support for cross-compiling and IPv6 support, as well as an ipc_stress test and a pthreads_stress test. Manoj Iyer and Paul Larson also wrote some changes to support architecture independence. Release notes for the new version are available through the project site on SourceForge.

"The Linux Test Project is a group aimed at testing and improving Linux," notes the team. "The goal of the LTP is to deliver a suite of automated testing tools for Linux as well as publishing the results of tests we run."

Miscellaneous patches
Following are miscellaneous patches produced by members of the LTC, beginning with the most recent. All of them have been submitted to the Linux Kernel mailing list.

• A BKL Removal patch by Dave Hansen moves the module ref count increment up, so that BKL isn't necessary.
• A GCOV kernel support patch by Hubertus Franke and Rajan Ravindran "enables GCOV, a test coverage program which helps discover where your optimization efforts will best affect your code, to be used with the Linux Kernel," notes Hubertus and Rajan.
• A new MCS locks patch has been updated by John Stulz to have a nodeless extension lock. "This can be used as a drop-in replacement for spinlocks. I did this by serializing access to a single bit lock with an MCS lock, keeping node allocation on the stack of nmcs_lock()," explains John. "This causes some additional overhead, but simplifies the usage."

OpenAFS
The OpenAFS project has released version 1.2.2b and 1.2.3. Many detailed changes have been made in the latter, all of which are documented in the changelog. The 1.2.2b release features a few minor changes that apply only to Windows ports and are detailed on the project home page.

AFS is a distributed enterprise file system with a data management model that was open sourced by IBM's Transarc lab in September of 2000. It offers a client-server architecture for file sharing in which files stored in AFS are accessed through user installations.

Open Source Cluster Application Resources (OSCAR)
The OSCAR clustering project has released version 1.2.1, which was developed with RedHat 7.1 as its base. Work is underway to support RedHat 7.2, as well as ia64, in the upcoming version 1.3. The fully tested OSCAR 2.0 is scheduled for release in the fall of 2002.

OSCAR is an integrated software bundle for building, programming, and using clusters. Components include LAM/MPI, LUI, OpenSSH, OpenSSL, and the System Installation Suite. OSCAR 1.0 was released in February of 2001 and was developed with RedHat 6.3 as its base. In the 1.2 beta release, the LUI installer was replaced with the full System Installation Suite, which was formed through the merger of LUI and the VA SystemImager. OSCAR is the first project developed by the Open Cluster Group led by IBM, Intel, Oak Ridge National Laboratory, Indiana University, University of Illinois' National Center for Supercomputing Applications, Dell, SGI, MSC.Software, and Veridian.

Performance Co-Pilot
A new Performance Co-Pilot patch for uptime metrics has been written by Mike Mason and accepted by the maintainer to be included in the next release. "This is a minor patch," according to Mike, "to change the kernel.all.uptime metric units from hours to seconds. This change was necessary to convert top and libgtop to use PCP for data gathering."

"Performance Co-Pilot (PCP) is a framework and services to support system-level performance monitoring and performance management," according to Ken McDonell of SGI. "The PCP open source release provides a unifying abstraction for all of the interesting performance data in a system, and allows client applications to easily retrieve and process any subset of that data using a single API. The open source release of PCP provides a subset of the features of SGI's Performance Co-Pilot products for IRIX."

Samba
Jim McDonough has written three new Samba patches, all of which have been committed in CVS:

• A patch against the Samba CVS (HEAD branch) "adds a net subcommand, printer, which allows publishing of the required fields of a printQueue object into an Active Directory server," notes Jim. "It also can retrieve information or delete from the directory a printQueue object.
• A Shareadd patch against the Samba_2_2 Branch enables RAP remote clients to issue a share add to the samba server.
• Another patch against the CVS (HEAD branch) enables the net command to use existing kerberos tickets. "If the user does not specify a username on the command line with the -U flag when doing a net ads command, it will first attempt to do the operation using existing kerberos credentials," Jim explains. "If no valid current credentials exist, or the command fails, it will then prompt for a password and try to obtain credentials using the current userid. If a username is specified with -U, it will always prompt for a password and try to obtain credentials with that username/password."

In other Samba news, version 2.2.3a was released in early February. It includes a bug fix for Windows Explorer over the 2.2.3 release, as well as some more general scaling bug fixes. "The 2.2.3 release had a problem with Windows 2000 Explorer in which copying files into a share that already existed failed with "Access Denied" rather than asking the user whether an overwrite was required," according to the Samba Team. "This was due to an incorrect error mapping between the UNIX EEXIST error code and the NT status error."

Miscellaneous news
Suparna Bhattacharya has written extensive design notes on asynchronous I/O for Linux (aio). The notes cover everything from motivation for the project to design philosophy, interfaces, and performance characteristics. "The POSIX spec has examples of using aio in a journalization model, a data acquisition model, and in supercomputing applications," writes Suparna. "Aio enables an application to keep a device busy (for example, raw i/o), potentially improving throughput. While maximum gains are likely to be for unbuffered i/o case, aio should be supported by all types of files and devices in the same standard manner. Besides, being able to do things like hands off zero-copy async sendfile, it can also be quite useful for streaming content servers."

Resources

• Read the previous LTC bulletins on developerWorks:
  • February 14, 2002
  • January 31, 2002
  • January 23, 2002
  • December 12, 2001
  • November 28, 2001
  • November 15, 2001
  • October 30, 2001
  • August 30, 2001
  • August 22, 2001
  • July 31, 2001
  • July 16, 2001
  • June 19, 2001
  • May 21, 2001
  • May 7, 2001
  • April 23, 2001
• Visit the Linux Technology Center and take a look Behind the scenes at the LTC.
• Browse the Linux Documentation Page.
• Learn more about the projects and patches covered in this LTC bulletin:
  • Internationalization patches (I18N) (developerWorks)
  • JFS project (developerWorks)
  • Linux Scalability Effort (SourceForge)
  • Linux Standard Base project (Free Standards Group)
  • Linux Test Project (SourceForge)
  • Miscellaneous patches (developerWorks)
  • OpenAFS project (OpenAFS.org)
  • OSCAR project (SourceForge)
  • Performance Co-Pilot (developerWorks)
  • Samba patch (developerWorks)
• Take our free JFS fundamentals tutorial.
• Check out more Linux resources and more Open source resources on developerWorks.

About the author
Maya Stodte, previously a contributing writer and editor for developerWorks, is now working as a freelancer. She can be reached at mstodte@yahoo.com.

Copyright 2002