LTTng Toolchain 2.4.0 is out!
Hi all!
After five release candidates, the LTTng 2.4 stable release, codenamed Époque Opaque, is finally ready!
LTTng Tools 2.4.0
The most important feature of this 2.4 release is the addition of live tracing support. A trace reading client may now connect to the relay daemon to read a trace as it is produced by both kernel and user space tracers.
Here is a short guide demonstrating this feature using Babeltrace v1.2.0:
lttng create my_session --live lttng enable-event --kernel --all lttng start
Active sessions can then be listed using Babeltrace:
babeltrace -i lttng-live net://localhost
which will output something like:
net://localhost/host/Hostname/my_session (timer = 1000000, 5 stream(s), 0 client(s) connected)
Then, a connection can be established:
babeltrace -i lttng-live net://localhost/host/Hostname/my_session
See the
live reading how-to
and the
create session
section in lttng
's man page for more information on this feature.
Another major feature added as part of this release is
Java Util Logging (JUL) support. It is now possible to enable events
in the new JUL domain. These events are produced using LTTng-UST's
new JUL backend. More information is available in
lttng
's manpage.
Finally, user space event exclusion has been added to lttng
's
enable-event
command which allows users to exclude events even if
wildcards are used. This feature is also usable with the --all
option.
LTTng-UST 2.4.0
This release brings Java Util Logging tracing to LTTng-UST. A new
library, liblttng-ust-jul
, provides a JUL LogHandler
implementation
along with the necessary shim to trace events from Java applications.
More information is available
here,
along with an
example.
Also of note, shared object base-address tracing has been added as
an experimental feature. This feature allows trace readers to perform
address to symbol mappings on dynamically loaded libraries by
generating the ust_baddr:push
and ust_baddr:pop
events on calls
to dlopen()
and dlclose()
.
See the lttng-ust-dl
manpage for more details.
Noteworthy changes:
- Added tracing instrumentation for pthread mutex lock functions
- Added event exclusion-list support
LTTng-Modules 2.4.0
Noteworthy changes:
- Addition of a new tracepoint in KVM (kvm_write_tsc_offset)
- Blacklist ARM gcc 4.8.0, 4.8.1, 4.8.2
Please feel free to email the list about any questions/comments
concerning this release at lttng-dev@lists.lttng.org
. For bugs or
missing documentation, use our bug tracker.
As always you can find the different packages in the Download section.