This document describes the changes made to the Observer application.

## Observer 2.14

### Fixed Bugs and Malfunctions

A WX event race could causes a crash in when handling socket or port info.

Own Id: OTP-18339

### Improvements and New Features

Improve the nodes menu to include more nodes.

Own Id: OTP-18269 Aux Id: PR-6030

## Observer 2.13

### Improvements and New Features

Fixed units in gui.

Own Id: OTP-18151 Aux Id: PR-6063

## Observer 2.12

### Fixed Bugs and Malfunctions

Fixed default handling of Mac specific menus.

Own Id: OTP-17996 Aux Id: PR-5795

Reading port socket options on macOS and Windows "skips" invalid options.

Own Id: OTP-18012 Aux Id: #5798

### Improvements and New Features

The configuration files .erlang, .erlang.cookie and .erlang.crypt can now be located in the XDG Config Home directory.

See the documentation for each file and filename:basedir/2 for more details.

Own Id: OTP-17554 Aux Id: GH-5016 PR-5408 OTP-17821

## Observer 2.11.1

### Fixed Bugs and Malfunctions

Fixed node information lookup for remote process identifiers in crashdump_viewer.

Own Id: OTP-17995 Aux Id: PR-5804

## Observer 2.11

### Improvements and New Features

Calculate the display width in etop, instead of hard-coding it to 89 characters.

Own Id: OTP-17880 Aux Id: PR-5557

## Observer 2.10.1

### Fixed Bugs and Malfunctions

Fix bug in crash dumps where the stackframe of a process would be printed using an incorrect format.

Crash dump viewer has also been fixed to be able read the broken stack format.

The bug has existed since Erlang/OTP 23.0.

Own Id: OTP-17814 Aux Id: PR-5462

## Observer 2.10

### Fixed Bugs and Malfunctions

Atoms with Unicode code points greater than 255 (for example Greek or Cyrillic characters) would not be displayed correctly by crashdump_viewer.

Own Id: OTP-17377

Fix the crashdump_viewer to be able to parse monitor_node/2 monitors correctly.

Own Id: OTP-17425 Aux Id: PR-4799

### Improvements and New Features

Observer now has a sectiion for new socket.

Own Id: OTP-17346

Added a trace all button to the trace window.

Own Id: OTP-17520 Aux Id: PR-4962

## Observer 2.9.6

### Improvements and New Features

Updated gui parts to work with the new wx version.

Own Id: OTP-17214

## Observer 2.9.5

### Fixed Bugs and Malfunctions

Fix graph windows flickering on windows.

Own Id: OTP-16778

## Observer 2.9.4

### Improvements and New Features

Minor updates due to the new spawn improvements made.

Own Id: OTP-16368 Aux Id: OTP-15251

## Observer 2.9.3

### Fixed Bugs and Malfunctions

Crashdump Viewer how handles crash dumps where the Old Binary VHeap has overflowed.

Own Id: OTP-16296

## Observer 2.9.2

### Fixed Bugs and Malfunctions

Fix bug after a user followed link on a pid from an expanded term window.

Own Id: OTP-15980 Aux Id: PR-2201

### Improvements and New Features

Improved dark mode colors on Linux.

Own Id: OTP-15916 Aux Id: ERL-921

## Observer 2.9.1

### Fixed Bugs and Malfunctions

All incorrect (that is, all) uses of "can not" has been corrected to "cannot" in source code comments, documentation, examples, and so on.

Own Id: OTP-14282 Aux Id: PR-1891

## Observer 2.9

### Fixed Bugs and Malfunctions

Since Logger was introduced in OTP-21.0, menu choice Log > Toggle Log View in observer would cause a crash unless an error_logger event handler was explicitly installed. This is now corrected.

Own Id: OTP-15553 Aux Id: ERL-848

### Improvements and New Features

Since persistent_term was introduced, observer would sometimes crash when expanding a term from a process state. This is now corrected.

Own Id: OTP-15493 Aux Id: ERL-810

Add OBSERVER_SCALE environment variable for HiDPI support.

Own Id: OTP-15586 Aux Id: PR-2105

## Observer 2.8.2

### Fixed Bugs and Malfunctions

Literals such as #{"one"=>1} dumped to a crash dump would cause crashdump_viewer to crash.

Own Id: OTP-15365 Aux Id: ERL-722

crashdump_viewer would sometimes crash when processing a dump which was truncated in the literals area. This is now corrected.

Own Id: OTP-15377

Since OTP-20.2, crashdump_viewer was very slow when opening a crash dump with many processes. An ets:select per process could be removed, which improved the performance a lot.

A bug when parsing heap data in a crashdump caused crashdump_viewer to crash when multiple Yc lines referenced the same reference counted binary. This is now corrected.

Own Id: OTP-15391

## Observer 2.8.1

### Fixed Bugs and Malfunctions

Improved documentation.

Own Id: OTP-15190

## Observer 2.8

### Fixed Bugs and Malfunctions

Added possibility to garbage collect selected processes and fixed a crash when the saved config file contained bad data.

Own Id: OTP-14993 Aux Id: PR-1666

### Improvements and New Features

Use uri_string module instead of http_uri.

Own Id: OTP-14902

## Observer 2.7

### Fixed Bugs and Malfunctions

etop.hrl used a relative path to include observer_backend.hrl, this is now changed to use include_lib instead. runtime_tools/include is added to the tertiary bootstrap.

Own Id: OTP-14842 Aux Id: ERL-534

If a crashdump was truncated in the attributes section for a module, crashdump_viewer would crash when a module view was opened from the GUI. This bug was introduced in OTP-20.2 and is now corrected.

Own Id: OTP-14846 Aux Id: ERL-537

Optimized ets and mnesia table view tab in observer gui, listing 10000 tables was previously very slow.

Own Id: OTP-14856 Aux Id: ERIERL-117

### Improvements and New Features

When a process has many links and/or monitors, it could earlier take very long time to display the process information window. This is now improved by only showing a few links and monitors, and then an link named "more..." to expand the rest.

Own Id: OTP-14725

More crash dump info such as: process binary virtual heap stats, full info for process causing out-of-mem during GC, more port related info, and dirty scheduler info.

Own Id: OTP-14820

## Observer 2.6

### Fixed Bugs and Malfunctions

A bug introduced in OTP-20 would make Crashdump Viewer crash when trying to expand an empty binary. This is now corrected.

Own Id: OTP-14642

If a match spec in the config file contained more than one clause, observer would earlier crash when trying to display it in the GUI. This is now corrected.

Own Id: OTP-14643 Aux Id: ERL-489

Writing of crash dumps is significantly faster.

Maps are now included in crash dumps.

Constants terms would only be shown in one process, while other processes referencing the same constant term would show a marker for incomplete heap.

Own Id: OTP-14685 Aux Id: OTP-14611, OTP-14603, OTP-14595

### Improvements and New Features

Binaries and some other data in crash dumps are now encoded in base64 (instead of in hex), which will reduce the size of crash dumps.

A few bugs in the handling of sub binaries in crashdump_viewer have been fixed.

Own Id: OTP-14686

In order to allow future improvements, Crashdump Viewer now checks the version tag of the crashdump to see that it is a known format. If the crashdump version is newer than Crashdump Viewer is prepared to read, then an information dialog is displayed before Crashdump Viewer terminates.

If an incomplete process heap is discovered in a crashdump, Crashdump Viewer will now display a warning for this, similar to the warning displayed when a crashdump is truncated. Incomplete heaps can occur if for instance the literals are not included, which is the case for all dumps prior to OTP-20.2.

Own Id: OTP-14755

## Observer 2.5

### Improvements and New Features

The following improvements are done to Crashdump Viewer:

Reading of crash dumps with many binaries is optimized. A progress bar is shown when the detail view for a process is opened. The cdv script now sets ERL_CRASH_DUMP_SECONDS=0 to avoid generating a new crash dump from the node running the Crashdump Viewer. A warning dialog is shown if the node running the Crashdump Viewer could potentially overwrite the crash dump under inspection. Bugfix: In some situations, Crashdump Viewer could not find the end of the 'Last calls' section in a crash dump, and would erroneously mark the crash dump as truncated. This is now corrected. Bugfix: In some situations, process info for a specific process would be marked as truncated by Crashdump Viewer, even if the crash dump was truncated in the binary section - and not related to the process in question. This is now corrected.

Own Id: OTP-14386

General Unicode improvements.

Own Id: OTP-14462

Tools are updated to show Unicode atoms correctly.

Own Id: OTP-14464

Add system statistics and limits to frontpage in observer.

Own Id: OTP-14536

## Observer 2.4

### Fixed Bugs and Malfunctions

etop had a hardcoded timeout value of 1 second when waiting for data from a remote node. When this expired, which could happen for instance if there were very many processes on the remote node, etop would exit with reason connection_lost. To overcome this problem, the timeout is now changed to be the same as the update interval, which is configurable.

Own Id: OTP-14393

### Improvements and New Features

Show dirty-scheduler threads in performance monitor graph and add a column with maximum allocated memory in the Memory Allocators table.

Own Id: OTP-14137

Keep table and port selection after refresh of tables. Store settings before shutdown and restore when starting application.

Own Id: OTP-14270

Miscellaneous updates due to atoms containing arbitrary Unicode characters.

Own Id: OTP-14285

When observing a node older than OTP-19.0, a pop-up will be displayed when trying to access port information. Earlier, observer would crash in this situation.

Own Id: OTP-14345 Aux Id: ERL-399

## Observer 2.3.1

### Fixed Bugs and Malfunctions

etop erroneously reported the average scheduler utilization since the tool was first started instead of the scheduler utilization since last update. This is now corrected.

Own Id: OTP-14090 Aux Id: seq13232

crashdump_viewer crashed when the 'Slogan' had more than one line. This is now corrected.

Own Id: OTP-14093 Aux Id: ERL-318

When clicking an HTML-link to a port before the port tab has been opened for the first time, observer would crash since port info is not initiated. This is now corrected.

Own Id: OTP-14151 Aux Id: PR-1296

The dialyzer and observer applications will now use a portable way to find the home directory. That means that there is no longer any need to manually set the HOME environment variable on Windows.

Own Id: OTP-14249 Aux Id: ERL-161

## 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