recon
=====
Recon wants to be a set of tools usable in production to diagnose Erlang problems or inspect production environment safely.
To build the library:
rebar3 compile
Documentation for the library can be obtained at http://ferd.github.io/recon/
It is recommended that you use tags if you do not want bleeding edge and development content for this library.
Current Status
--------------
[](https://travis-ci.org/ferd/recon)
Versions supported: OTP-17 and up. Support of R16B03-1 down to R15B02 is best effort. Builds with Rebar3 require OTP-17.1 and up because that's what the tool supports.
Changelog
---------
Branches are organized by version. `master` contains the bleeding edge, `2.x`
contains all stable changes up to the latest release of v2, and `1.x` contains
all stable changes of the first version of Recon.
*2.x*
- 2.5.1
- Fix support for extra messages in traces (thanks to Péter Gömöri)
- Fix some typespecs for match specs (thanks to @chenduo)
- Support OTP-23 change of format in allocator blocks related to carrier migration support
- 2.5.0
- Optional formatting of records in traces (thanks to @bartekgorny)
- Basic support for OTP-22 in `recon_alloc` (base handling of `foreign_blocks` type)
- 2.4.0
- Optional formatting of records in traces (thanks to @bartekgorny)
- 2.3.6
- Adapting for OTP-21. Includes the 'deprecation' of `recon:files/0`
since OTP-21 no longer supports listing all file descriptors, and
removing `error_logger_queue_len` from node stats since a new
logging mechanism was introduced in-process instead.
- 2.3.5
- fixing timefold's first iteration to prevent errors at call-site
by sleeping before sampling
- 2.3.4
- fixing edoc tag that broke some downstream packaging attempts
- 2.3.3
- fixing `bin_leak` arith errors
- fixes to `recon_alloc:allocators/1` (incl. R16 compatibility)
- fix errors in scheduler wall time calculations
- `term_to_pid` supports binaries
- 2.3.2
- Allow the `return_to` option in `recon_trace`
- More efficient sorting function for procs and ports attributes
(thanks to @zhongwencool and @pichi)
- Allow the usage of `return_trace` in `recon_trace:calls/2-3` instead
of `fun(_) -> return_trace() end`.
- 2.3.1
- Updated `app_deps` script to run with rebar3 dependencies
- Minor docs update
- 2.3.0
- Doc made clearer around semantics of `recon:proc_count` and
`recon:proc_window`.
- Fix doc typos
- Fix potential race condition on waiting for death of tracing process
- Add an option which allows sending tracing output somewhere other than
group_leader() (thanks @djnym)
- Add ability to pass custom formatter function when tracing (thanks @iilyak)
- 2.2.1
- Fixing type specs for `recon:port_types/0` and `recon_lib:count/1`,
thanks to @lucafavatella
- Minor documentation fixes.
- 2.2.0:
- Adding scheduler info metrics to get a more accurate picture than what
top and CPU gives.
- Broadening `recon_trace:calls/2` interface to allow multiple match specs,
which was currently only allowed for `calls/3`.
- Support for `mbcs_pool` data in `erts_alloc`, and some internal refactoring,
thanks to Lukas Larsson.
- 2.1.2:
- Fixing tests for R15B02 and up
- Fixing a backwards compatibility for R15B03 on `recon_alloc` operations
with dumps on disk
- 2.1.1:
- Renaming `recon_trace:mfa()` type to `recon_trace:tspec()` to avoid
issues in older Erlang versions regarding redefining an existing type
(Thanks Roberto Aloi)
- 2.1.0:
- Adding `recon_trace` script to allow safe tracing of function calls
on production nodes.
- Adding `queue_fun.awk` script to inspect running functions of processes
with large mailboxes in a crash dump.
- 2.0.2:
- Preventing crashes in `recon_alloc` when certain expected allocators
do not return results (Thanks to Michal Ptaszek)
- 2.0.1:
- Add support for R16B03 in `recon_alloc`.
- 2.0.0:
- Test suite added
- Major rewrite of `recon_alloc`, thanks to Lukas Larsson. Things that changed include:
- `average_sizes/0` is renamed `average_block_sizes/1` and now takes
the keywords `current` and `max`.
- Documentation updates.
- `memory/1` has new options in `allocated_types` and `allocated_instances`.
- `memory/2` has been added, which allows to choose between `current` and
`max` values. `memory(Term)` is made equivalent to `memory(Term, current)`.
- Allow `sbcs_to_mbcs/0` to take the arguments `current` and `max`.
- Added unit conversion function `set_unit/1`, which allows to get the
`recon_alloc` results in bytes (default), kilobytes, megabytes, and
gigabytes, to help with readability.
- Updated the internal rebar version, if anybody were to use it.
- `recon:port_info/1` no longer includes the `parallelism` option by default
within the `meta` category as this would hurt backwards compatibility on
some installations.
- `recon:get_state/2` is added in order to specify timeouts.
`recon:get_state/1` keeps its 5000 milliseconds timeout.
- Addition of a fake attribute called `binary_memory`, which is callable in
`recon:info/2,4`, `recon:proc_count/2`, and `recon:proc_window/3`. This
attribute allows to fetch the amount of memory used by refc binaries for
a process, and to sort by that value for counts and windows.
*1.x*
- 1.2.0:
- add `recon_alloc:snapshot*` functions, which allow memory allocation
snapshots to be taken, saved on disk, reloaded, and analyzed on-demand.
Thanks to Lukas Larsson for this functionality.
- remove `parallelism` data from `port_info` for better OTP backwards
compatibility with little loss of information.
- 1.1.0:
- add `recon_lib:term_to_port` to convert a string back to a
usable port.
- add `recon:port_info/1` and `recon:port_info/2`
- add `recon_alloc` module
- 1.0.0: add `info/2` and `info/4`. The `memory` info type thus gets renamed
to `memory_used`, in order to avoid conflicts when picking between a type
and a specific process attribute. Types exported by the module also get
updated.
- 0.4.2: extended `app_deps.erl` to read apps/ directories for releases
- 0.4.1: fixed bug where nodes with lots of processes could see the GC call
fail if said processes failed between long calls within the `bin_leak`
function call.
- 0.4.0: fixed bug where nodes with lots of processes or ports could see their
count or window functions fail because a process or socket closed between the
time the function started and before it finished. This ends up changing the
API in `recon_lib` for the window and count functions that take a specific
pid as an argument.
- 0.3.1: factored out some logic from `recon:info/1` into `recon_lib:term_to_pid`
and allowed arbitrary terms to be used for pids in `recon:get_state/1`.
