[Fkt-devel] New alternative to FxT

[François Trahay]

Dear FxT users,
I have used FxT for a long time now, especially in the EZTrace project. 
However, recent projects in EZTrace made us reconsidere FxT for several 
reasons:
- the 2-level tracing system (for both kernel and user-space) in FxT makes the 
source code complex to understand/maintain.
- we (ie. the EZTrace project) only use the user-level tracing mechanism.
- several scalability issues in FxT (for instance, the contention when a large 
number of threads record events concurrently) require a serious code 
refactoring.

For these reasons, we decided to create a new tracing library called LiTL 
(LightWeight Trace Library). This library is similar to FxT on several points:
- it provides the same user-level ytracing mechanism
- the API is almost the same. This permits to port an application from FxT to 
LiTL with little effort

However, it differs from FxT for the following reasons:
- it only works for user-level tracing.
- it is easier to maintain/improve
- the generated trace files are smaller
- a mechanism improves the scalability when the number of concurrent threads 
increases.

The first version of LiTL (v0.1) is available under the BSD license on Telecom 
SudParis forge:
https://fusionforge.int-evry.fr/frs/?group_id=36

We'd like your opinion on the project as well as on the API we propose. Any 
remark/contribution to the API/implementation would also be greatly 
appreciated :-)

François Trahay