LTTng-modules and LTTng-UST 2.10.0 (KeKriek)

Hi,

Today, we release the 2.10 stable versions of LTTng kernel and user-space tracers. This release is named "KeKriek", which is a sour mashed golden wheat ale brewed by the Dunham microbrewery in Quebec.

The new features included are:

- A new "blocking" mode for LTTng-UST (it has been requested for a while). It blocks application tracing when buffers are full (for "discard mode tracing") rather than discarding events, until a user-specified timeout is reached (or indefinitely). It affects only applications launched with the LTTNG_UST_ALLOW_BLOCKING environment variable set, and channels configured with the "--blocking-timeout" option. See lttng-ust(3) for usage information.

This feature is useful if you intend to trace huge amounts of data from applications (e.g. all memory allocation/free, or detailed execution of a simulator) in use-cases where it is acceptable to block the traced application.

- Add support for multiple star-globbing patterns in LTTng-UST and LTTng-modules. Now events can be enabled with a pattern containing many wildcards, e.g. 'sche*_sw*t*h'. Those can also be used when comparing strings with filter, e.g.:
lttng enable-event -u myevent --filter 'myfield == "abc*d*e*fg"'

- LTTng modules adds support for kernels 4.10, 4.11, 4.12 (which has been backported to 2.8 and 2.9 stable branches).

- LTTng modules adds the task CPU in threads state dump, improving precision of the scheduler model.

- LTTng modules now collects extend socketpair system call tracing data.

For more information on new features introduced in this version,
see: http://lttng.org/docs/v2.10/#doc-whats-new

The 2.10.0 release marks the end of life for the old stable-2.8 branches. There will be one last stable-2.8 release for both lttng-modules and lttng-ust, after which they will become unsupported.

Project website: http://lttng.org
Documentation: http://lttng.org/docs
Download link: http://lttng.org/download

Changelog:

2017-08-01 (World Wide Web Day) LTTng modules 2.10.0
* Fix: Sleeping function called from invalid context
* Fix: sched for v4.11.5-rt1
* Fix: handle missing ftrace header on v4.12

2017-08-01 (World Wide Web Day) lttng-ust 2.10.0
* lttng-ust(3): reword and fix style of LTTNG_UST_ALLOW_BLOCKING variable
* lttng-ust(3): specify "If set" instead of "if set to 1" for some variables
* Fix: doc/man: use a single XSL file and match local names
* Fix: Expand the shmobj size for the sequence number

Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com