NPTL (Native POSIX Threading Library) Tests and Trace



Date News


Our server has changed, which should result in better speed of this web site.


The final report for the second Test Campaign, as well as the project, is available in the Papers section of the site. Direct link


A few changes to this website, for a clearer presentation (I hope). All documents (including OLS material) are now located in the Papers section.


A new test campaign is on its way. The results will be added to the results database. It will serve as a base to fix some remaining problems both in nptl and in the test suite. More details will come later.

The forum is closed now. No new message can be posted; but old messages can still be read.


The schedule for the Ottawa Linux Symposium has been posted! (Here). As you can see, we'll be giving our presentation on Saturday the 23rd, at noon. Come and see us ;)


Here is an extract from Fedora Core 4 release notes:

" As the next step in removing support for the obsolete LinuxThreads library,
 code compiled and linked on Fedora Core 4 now
 automatically uses the NPTL headers and libraries.

In previous releases since Red Hat Linux 9, the default threading was LinuxThreads
 since the interface is mostly forward compatible. 
The advantages of the NPTL interface is that the cancellation handling is faster 
(when -fexception is used, even in C code) and that the additional 
interfaces are now available without special compiler and linker parameters. 
In other words, you do not need to use
 -I/usr/include/nptl and -L/usr/lib{,64}/nptl
 any longer. Note that lib{,64} is to be interpreted as lib64 
on platforms which place DSOs in lib64/ directories, 
and lib/ otherwise. "


New PTT released! This new release brings some new features and adds support for IA64 and PPC architectures. See project homepage for more information.


ptt-beta1 was released last week. This is a beta release, meaning almost all functionnalities are added and the interface should not change a lot from now on. Have a look at the tool webpage for more information and documentation.


Long time since previous news... In the meantime, the website has been updated to include links to the PTT project (was previously known as NPTL Trace project). See links section for more information.

The PTT release alpha3 is out. See this URL for release notes and downloads. Thanks to contributors!


The latest testcase for sem_unlink has just been written. So, test writting for P2 function list is complete.


Four functions, related to Thread-Local Data (TLD) have been downgraded from P2 to P3 list: pthread_key_create, pthread_getspecific, pthread_setspecific and pthread_key_delete. These functions are not used really often in Linux, as gcc provides the __thread keyword which offers better performances and simpler use.

As the sem_unlink analysis has just been written, the P2-routines list is now completed. In a few days, all tests should be written and completed, and the final test campaign can start.


The news just felt: We'll give a presentation on our NPTL Test & Trace project at the Ottawa Linux Symposium. See this web site for more information on the symposium.


The forum subscription has been disabled temporarly because of an exploit in phpBB allowing any user to log in as administrator. No new user accepted until this issue is fixed.

Actually the issue is already solved in phpBB 2.0.13, the forum has been updated, subscription is reopened.


Two new problems have been found in the NPTL. The first one is a conformance problem: sem_open() returns a wrong error code when there is no space left. This has been reported as bug 774 in bugzilla. The second one is a scalability issue with sem_close. See the graphical example. This has not been reported, as explained in the Results section.


We've passed the 10.000 hits on this site, a few days ago! (and the forum's hits do not count into this). The statistics (not available to public) show that most people come from a google site...

As for the progress, the thread cancelation functions are almost done. Remaining are the semaphores and the thread-local data functions, before priority 2 completion.


See full archive of the news.


Page maintained by: Tony Reix