[lttng-dev] [RELEASE] LTTng-Tools 2.6.0 - Gaïa

[Jérémie Galarneau]

Hi all,

I am thrilled to announce the stable release of LTTng-Tools 2.6.0 is
finally available!

LTTng-Tools 2.6 introduces three major new features:

* Client machine interface (MI) *

This feature, contributed by project newcomer Jonathan Rajotte,
introduces a new option (--mi TYPE) which can be used in conjunction
with all LTTng client commands to produce a machine output instead of
the regular pretty-printed output typically emitted by the client. As
of this release, the only available MI format is XML. A schema
definition (XSD) is made available to ease validation and integration
as much as possible.

In essence, this interface is being added to streamline the
development of client usability improvements since external tools can
now depend on a stable, versioned, interface. Therefore, it will now
be easier to improve the client's UI in future release without fear of
breaking users' workflow.

Amazingly, TraceCompass and the LTTng bash completion script have
already started using this new machine interface!


* Introducing Java Log4J support *

A new Log4J domain has been introduced (-l/--log4j) and may be used
the same way as the other supported domains, namely userspace
(-u/--userspace), kernel (-k/--kernel) and JUL (-j/--jul).

Based on the work done to support the Java Util Logging framework,
this new domain allows users to use LTTng as a LogAppender in
applications using the Log4J logging framework.

Log4J events can now be enabled using:

$ lttng enable-event -l my_event


* Per-System call tracing *

While LTTng has supported system call tracing for a while, this
release introduces per-syscall tracing which makes it possible to
enable only a subset of available syscalls. This has the benefit of
greatly reducing required tracing bandwidth in scenarios where only a
few system calls are of interest.

A list of available syscalls can be obtained using:

$ lttng list -k --syscall

Individual system calls can then be enabled using:

$ lttng enable-event -k --syscall open


We will make sure to cover these features in greater detail in an
upcoming blog post on the official LTTng website; stay tuned!

On top of these features, 31 fixes have made it into this release
since the Release Candidate 4 release on December 12th.

2015-01-26 lttng-tools 2.6.0 (Paul the Octopus is born)
        * Tests: Run health check test_thread_ok as part of root_regression
        * Fix: deadlock between UST registry lock and consumer lock
        * Fix: uninitialized return value
        * Fix: build failure using disable-lttng-ust configure option
        * Fix: grab more than one packet for snapshots
        * Fix: per-uid flush and ust registry locking
        * Fix: add missing synchronization point for before app test case
        * Fix: tests: wait output hide Terminate errors
        * Fix: tests: remove killall, add missing SIGTERM handlers
        * Fix: high throughput test: reset bw limit on sigterm
        * Fix: tests: add missing wait, document missing synchro
        * Document test anti-patterns
        * Fix: test flaky sleep and wait patterns
        * Fix: tests: don't use pidof to wait for test apps
        * Docs: Grammar fixes in the lttng manpage
        * Fix: add missing UST perf counter support check
        * Fix: tests: integer too large for long type
        * Fix: undefined operation on last_relay_viewer_session_id
        * Fix: print format type mismatch
        * Fix: print format type mismatch
        * Fix: Remove unused argument in debug statement
        * Cleanup: Remove unused label
        * Fix: exit threads not only on goto restart
        * Fix: poll: show the correct number of fds
        * Fix: compat poll: add missing empty revents checks
        * Fix: various compat poll/epoll issues
        * Fix: mi: snapshot: missing error handling for session name
        * Fix: ust-app: per-PID app unregister vs tracing stop races
        * Fix: data pending: allow empty streams
        * Fix: ust snapshot: cleanup after error
        * Fix: add missing RCU read unlock


As always, please report any issue you may encounter to bugs.lttng.org
or on this mailing list.

Project website: https://lttng.org

Download links:
https://lttng.org/files/lttng-tools/lttng-tools-2.6.0.tar.bz2
GPG sig: https://lttng.org/files/lttng-tools/lttng-tools-2.6.0.tar.bz2.asc

Looking forward to your feedback!
Jérémie

-- 
Jérémie Galarneau
EfficiOS Inc.
http://www.efficios.com