This document describes the changes made to the Observer application.

## Observer 2.3

### Fixed Bugs and Malfunctions

The shell script (priv/bin/cdv) and bat file (priv/bin/cdv.bat) which can be used for starting crashdump_viewer both started a distributed erlang node. This would cause any attempt at starting a second instance of the crashdump_viewer to fail. To solve this problem, cdv and cdv.bat now use non-distributed nodes when starting the crashdump_viewer.

Own Id: OTP-14010

A bug caused the number of buckets to be shown in the 'Objects' column, and the number of objects to be shown in the 'Memory' column for ets table in crashdump_viewer. This is now corrected.

Own Id: OTP-14064

### Improvements and New Features

Add option queue_size to ttb:tracer/2. This sets the maximum queue size for the IP trace driver which is used when tracing to shell and/or {local,File}.

The default value for queue_size is specified by dbg, and it is now changed from 50 to 200.

Own Id: OTP-13829 Aux Id: seq13171

The port information page is updated to show more information per port.

Own Id: OTP-13948 Aux Id: ERL-272

## Observer 2.2.2

### Fixed Bugs and Malfunctions

Fixed error handling in observer when mnesia tables was requested and not available.

Own Id: OTP-13845 Aux Id: ERL-237

## Observer 2.2.1

### Fixed Bugs and Malfunctions

Fixed a crash happening when observing another node, who have a different number of schedulers than the current one.

Own Id: OTP-13702 Aux Id: ERL-171

## Observer 2.2

### Improvements and New Features

Update observer GUI to support tracing on ports, and to set matchspecs for send/receive. This required some minor bugfixes in runtime_tools/dbg.

Own Id: OTP-13481

Update dbg and ttb to work with a tracer module as tracer and tracing on ports.

Own Id: OTP-13500

Added possibility to change update frequency and length of the graph windows.

Own Id: OTP-13555

Improved background coloring to work with dark themes and other visual improvements.

Own Id: OTP-13556

Crashdump viewer now allows port info "Port controls forker process..."

Own Id: OTP-13647

## Observer 2.1.2

### Improvements and New Features

Documentation corrections.

Own Id: OTP-12994

## Observer 2.1.1

### Fixed Bugs and Malfunctions

Show ets owner pid in crashdump viewers popup window, thanks Leo Liu.

Own Id: OTP-13030

Several initialisms (eg, ERTS, ETS, SMP) are used as headings. They were being capitalized incorrectly.

Own Id: OTP-13044

Fixed a crash in crashdump viewer when dump contained a truncated binary.

Own Id: OTP-13163

## Observer 2.1

### Fixed Bugs and Malfunctions

Show run queue status in crashdump viewer.

Own Id: OTP-12401

Don't refresh observer table view if there was no change

Own Id: OTP-12819

### Improvements and New Features

Added display of new crashdump information available in crashdumps from Erlang/OTP 18.

Own Id: OTP-12363

Added the possibility to view sasl log entries for processes.

Own Id: OTP-12504

Add memory allocator usage and utilization graphs.

Own Id: OTP-12631

## Observer 2.0.4

### Fixed Bugs and Malfunctions

Fix crash when opening a process information window.

Own Id: OTP-12634

## Observer 2.0.3

### Fixed Bugs and Malfunctions

A note saying only R15B nodes can be observed is removed from the user guide.

Own Id: OTP-12078

## Observer 2.0.2

### Fixed Bugs and Malfunctions

Fixed statusbar on Windows

Own Id: OTP-12162

## Observer 2.0.1

### Fixed Bugs and Malfunctions

crashdump_viewer would crash if the owner of a timer was specified as the process' registered name. This has been corrected.

Own Id: OTP-11919

Fix crash and minor updates.

Own Id: OTP-11949

## Observer 2.0

### Fixed Bugs and Malfunctions

etop trace handler now works in smp environment (Thanks to Péter Gömöri)

Own Id: OTP-11633

Application upgrade (appup) files are corrected for the following applications:

asn1, common_test, compiler, crypto, debugger, dialyzer, edoc, eldap, erl_docgen, et, eunit, gs, hipe, inets, observer, odbc, os_mon, otp_mibs, parsetools, percept, public_key, reltool, runtime_tools, ssh, syntax_tools, test_server, tools, typer, webtool, wx, xmerl

A new test utility for testing appup files is added to test_server. This is now used by most applications in OTP.

(Thanks to Tobias Schlager)

Own Id: OTP-11744

### Improvements and New Features

Removed gs based applications and gs based backends. The observer application replaces the removed applications.

*** POTENTIAL INCOMPATIBILITY ***

Own Id: OTP-10915

The crashdump_viewer is re-written using wx. The old webtool interface for crashdump_viewer does no longer exist.

*** POTENTIAL INCOMPATIBILITY ***

Own Id: OTP-11179

## Observer 1.3.1.2

### Fixed Bugs and Malfunctions

The documentation for ttb:tracer/2 incorrectly stated that there was an option named 'overload', while the correct name used in the implementation is 'overload_check'.

Own Id: OTP-11335 Aux Id: seq12385

Fixed typo in observer documentation. Thanks to Dave Parfitt.

Own Id: OTP-11475

## Observer 1.3.1.1

### Improvements and New Features

The encoding of the notes.xml file has been changed from latin1 to utf-8 to avoid future merge problems.

Own Id: OTP-11310

## Observer 1.3.1

### Fixed Bugs and Malfunctions

Some bugs related to calculation of CPU/scheduler utilization in observer are corrected.

Current function for a process is accepted to be 'undefined' when running hipe.

Own Id: OTP-10894

### Improvements and New Features

The new Memory field from a crash dump is now presented by crashdump viewer, both in the process overview and in the process detail page. A summary of blocks- and carriers sizes is added to the allocator information page in the crashdump viewer.

Own Id: OTP-10604 Aux Id: kunagi-336 [247]

Use "open" as default browser for crashdump viewer on Mac OS X. Thanks to Magnus Henoch.

Own Id: OTP-10929

Fix observer table viewer crash on formatting improper lists. Thanks to Andrey Tsirulev

Own Id: OTP-10931

Postscript files no longer needed for the generation of PDF files have been removed.

Own Id: OTP-11016

Add processes state view in observer. Thanks to Eric Pailleau.

Own Id: OTP-11136

## Observer 1.3

### Improvements and New Features

Where necessary a comment stating encoding has been added to Erlang files. The comment is meant to be removed in Erlang/OTP R17B when UTF-8 becomes the default encoding.

Own Id: OTP-10630

## Observer 1.2

### Fixed Bugs and Malfunctions

The module name in the link to the detail page for each loaded module was earlier not URL encoded. If the module name contained e.g. a # this could cause the crashdump viewer to crash when opening the link. This has been corrected.

Own Id: OTP-10090 Aux Id: seq12068

Escape control characters in Table Viewer

Similar behaviour to old tv. Objects in tables supposed to be printed in a single line and it looks ugly when a [...,10,...] integer list creates a new-line. Fix Table Viewer search crash on new|changed|deleted rows.

Fix Table Viewer crash after a 'Found' -> 'Not found' search sequence

Start position was lost after a 'Found' -> 'Not found' search sequence leading an undefined position in the next search. Thanks to Peti Gömori

Own Id: OTP-10218

observer: fix app file (Noticed-by: Motiejus Jakstys)

Add missing observer modules to observer.app.src. Thanks to Tuncer Ayaz.

Own Id: OTP-10221

Make Table Viewer search a bit faster

Edit table row in a multiline text dialog. Thanks to Peti Gomori.

Own Id: OTP-10225

### Improvements and New Features

Allow tracing on bifs.

Ask epmd for local nodes, and remember users last input in connect.

Fix crashes when a table or process information could not be retrieved.

Own Id: OTP-10075

## Observer 1.0

### Fixed Bugs and Malfunctions

The following bugs in ttb have been corrected:

ttb:tracer/2 would earlier crash when trying to set up tracing for a diskless node to wrap files, i.e. when option {file,{local,{wrap,Filename,Size,Count}}} was used. ttb:stop([fetch]) would sometimes silently fail if multiple nodes with different current working directories were traced. ttb:stop([fetch]) would crash if the tracer was started with option {file,{local,Filename}} A deadlock would sometimes occur due to an information printout from the ttb_control process when ttb was stopped.

Own Id: OTP-9431

The file trace port to which the IP trace client relays all traces from diskless nodes was not flushed and closed properly on ttb:stop. This has been corrected.

Own Id: OTP-9665

### Improvements and New Features

A new GUI for Observer. Integrating pman, etop, appmon and tv into observer with tracing facilities.

Own Id: OTP-4779

The following new features are added to ttb:

A one-command trace setup is added, ttb:start_trace/4. The following new options are added to ttb:tracer/2: shell - Show trace messages on the console in real time timer - Time constrained tracing overload - Overload protection flush - Flush file trace port buffers with given frequency resume - Automatically resume tracing after node restart A new shortcut is added for common tracer settings similar to using the dbg module directly, ttb:tracer(shell | dbg). Some shortcuts are added for commonly used match specifications in ttb:tp and ttb:tpl. The Options argument to functions ttb:tracer, ttb:write_config, ttb:stop and ttb:format may now be one single option instead of a list. The history buffer of the last trace is now always automatically dumped to the file ttb_last_config when ttb:stop is called. The following new options are added to ttb:stop/1: fetch_dir - Specify where to store fetched logs {format,FormatOpts} - Specify options to use when formatting the fetched logs return_fetch_dir - Indicate that the return value from ttb:stop/1 should include the name of the directory where the fetched logs are stored The option disable_sort is added to ttb:format/2. When this option is used, trace messages from different logs are not merged according to timestamps, but just appended one log after the other.

Own Id: OTP-9403

The following non backwards compatible changes are done in ttb:

When setting up trace with ttb, the 'timestamp' trace flag will now always be set. The 'fetch' option to ttb:stop/1 is removed since it is now default behavior that trace logs are fetched when stopping ttb. Fetching can be disabled with the 'nofetch' option to ttb:stop/1. The name of the upload directory is changed from ttb_upload-Timestamp to ttb_upload_FileName-Timestamp. To format the output using 'et', you now need to provide the option {handler,ttb:get_et_handler()} instead of {handler,et}. When formatting a trace log, the handler state was earlier reset after each trace file, this is now changed so the handler state is passed not only from one trace message to the next in the same file, but also from one file to the next.

*** POTENTIAL INCOMPATIBILITY ***

Own Id: OTP-9430

## Observer 0.9.10

### Fixed Bugs and Malfunctions

Do not install *.bat files on non-win32 machines (Thanks to Hans Ulrich Niedermann)

Own Id: OTP-9515

## Observer 0.9.9

### Improvements and New Features

The time needed for loading a crashump into the crashdump viewer would earlier grow exponentially with the size of the crashdump file. Reading a file of 20M would take a couple of minutes, and for a dump of 250M it would take between 1 and 2 hours. This has been solved.

Earlier, all processes, timers, funs or ets-tables would be loaded into the memory of the crashdump viewer node before sending it on to the web server. This has been changed and the pages are now sent to the web server in chunks.

A security function in newer web browsers prevents a full file path to be sent from an HTML file input field, i.e. the field needed to implement the "Browse" button when loading a file into the crashdump viewer. To overcome this, the file input field is no longer used. Instead a normal text input field is used, and the user needs to manually insert the complete file path. For convenience, a shell script and a batch file are added to the observer application. These can be used to start the crashdump_viewer and a browser and load a file - with the file name given from the command line. The shell script and batch file are called cdv and cdv.bat respectively, and can be found in the priv dir of the observer application.

Own Id: OTP-9051 Aux Id: seq11789

## Observer 0.9.8.4

### Improvements and New Features

The multitrace.erl installation example file is now installed in the examples directory. (Thanks to Peter Lemenkov.)

Own Id: OTP-8857

## Observer 0.9.8.3

### Improvements and New Features

The test suite has been updated for R14A.

Own Id: OTP-8708

## Observer 0.9.8.2

### Improvements and New Features

Misc updates

Own Id: OTP-8456

## Observer 0.9.8.1

### Improvements and New Features

Major improvements of the Erlang distribution for Erlang runtime systems with SMP support. Previously distribution port locks were heavily contended, and all encoding and decoding for a specific distribution channel had to be done in sequence. Lock contention due to the distribution is now negligible and both encoding and decoding of Erlang messages can be done in parallel.

The old atom cache protocol used by the Erlang distribution has been dropped since it effectively prevented all parallel encoding and decoding of messages passed over the same distribution channel.

A new atom cache protocol has been introduced which isolates atom cache accesses and makes parallel encoding and decoding of messages passed over the same distribution channel possible. The new atom cache protocol also use an atom cache size 8 times larger than before. The new atom cache protocol is documented in the ERTS users guide.

Erlang messages received via the distribution are now decoded by the receiving Erlang processes without holding any distribution channel specific locks. Erlang messages and signals sent over the distribution are as before encoded by the sending Erlang process, but now without holding any distribution channel specific locks during the encoding. That is, both encoding and decoding can be and are done in parallel regardless of distribution channel used.

The part that cannot be parallelized is the atom cache updates. Atom cache updates are therefore now scheduled on the distribution port. Since it is only one entity per distribution channel doing this work there is no lock contention due to the atom cache updates.

The new runtime system does not understand the old atom cache protocol. New and old runtime systems can however still communicate, but no atom cache will be used.

Own Id: OTP-7774

## Observer 0.9.8

### Improvements and New Features

etop would crash if the emulator's custom allocators had been turned off (e.g. using the +Meamin option).

Own Id: OTP-7519

The copyright notices have been updated.

Own Id: OTP-7851

## Observer 0.9.7.4

### Improvements and New Features

Minor Makefile changes.

Own Id: OTP-6689

Obsolete guard tests (such as list()) have been replaced with the modern guard tests (such as is_list()).

Own Id: OTP-6725

## Observer 0.9.7.3

### Improvements and New Features

This application has been updated to eliminate warnings by Dialyzer.

Own Id: OTP-6551

## Observer 0.9.7.2

### Fixed Bugs and Malfunctions

Several minor bugs and race conditions eliminated in the runtime_tools and observer applications.

Own Id: OTP-6265

## Observer 0.9.7.1

### Fixed Bugs and Malfunctions

Crash dump with large integers could crash the crashdump_viewer.

Own Id: OTP-6301

## Observer 0.9.7 (R11B)

### Fixed Bugs and Malfunctions

Fixed a bug in etop which made the Load and Memory information in the header incorrect -- for example the value shown for binary (memory allocated for binaries) was actually the number of currently running processes. (Thanks to Rikard Johansson.)

Own Id: OTP-6075

## Observer 0.9.6.2

### Fixed Bugs and Malfunctions

The Observer application has been recompiled because of a compiler bug.

Own Id: OTP-5700

## Observer 0.9.6.1

### Fixed Bugs and Malfunctions

crashdump_viewer is faster when showing message, dictionary, and stack dump for large processes.

Own Id: OTP-5408