The new Linux 2.4 kernel delivers much-needed improvements in core operating system functions such as memory management and performance scalability. And, as is the norm for Linux, front-line application developers, power coders and hackers will see these benefits first.
Linux 2.4, which became available Jan. 4, can be downloaded at www.kernel.org. However, as with past kernel releases, Linux users wont see new distributions from major Linux vendors, such as Red Hat Software Inc., for a few weeks or possibly a few months.
eWeek Labs suggests that readers wait for distributions before moving their systems to the new kernel. Developers working on long-term projects and those with prerelease Intel Corp. IA-64 Itanium workstations might want to use this release, bearing in mind that very little performance tuning has been done on Itanium systems. We used a desktop machine from Penguin Computing Inc. to run the kernel.
The 2.4 kernel isnt distributed in a packaged format such as a Red Hat Package Model yet, so IT managers who want to experiment with it must compile the source code and install it manually.
The core benefits of the 2.4 kernel are for high-end servers with multiple processors. In 2.4, the entire networking layer was rewritten to be more scalable. New "wake one" scheduling ensures only one process in a group of processes waiting for network traffic on the same socket gets scheduled for execution when network data arrives, a change that will aid the performance of most Linux server applications.
Memory support has also been improved, allowing Linux servers to address up to 64GB of memory, even when running on 32-bit Intel processors. Linux 2.4s shared memory management is also improved, which should lead to better performance.
In terms of Web serving, the new kernel Web daemon (kHTTPd) will significantly boost the performance of static content delivery because it will be able to field requests before they are sent to standard Web servers such as Apache.
Data storage should be much improved on Linux 2.4 servers because the RAID support was rewritten to take advantage of multiprocessor systems. A Journaling File System is still missing, although there are a few implementations (such as the Rieser File System) that could become the standard in point releases of the 2.4 kernel, most probably when distributions become available.
For low-end machines, the new support for USB should let more peripheral vendors create products for Linux desktops and workstations. In general, keyboards and mice are a safe bet to be recognized, but support for other devices, such as Diamond Multimedia Systems Inc.s Multimedia RIO 500 MP3 player, has not been finalized.
FireWire (IEEE 1394) support is included, but this is still in its infancy, so dont expect to see many FireWire products for Linux.