# Os_mon Release Notes

## Os_mon 1.6.1

### Fixed errors and malfunctions

- A configurable "helper timeout" has been added to `memsup`. It defines how long timeout time, in seconds, the `memsup` process should use when communicating with the `memsup_helper` process (an application internal server). The default is 30 seconds. The "helper timeout" can be set with the `memsup_helper_timeout` configuration parameter, or the `memsup:set_helper_timeout/1` function. `memsup:get_helper_timeout/0` can be used to retrieve the currently used "helper timeout".
  (Own Id: OTP-4223)
  (Aux Id: Seq7222)

- A bug which could cause memsup to be erroneously initialized has been fixed. The erroneous initialization could in turn cause the `system_memory_high_watermark` alarm to be set too early.
  (Own Id: OTP-4515)
  (Aux Id: OTP-4489)

## Os_mon 1.6.0

### Fixed errors and malfunctions

- Corrected return value from memsup:init/1 in error case.
  (Own Id: OTP-4289)

- process_memory_high_watermark alarm was erroneously set when 1/4 of the limit had been reached. This bug has now been corrected.
  (Own Id: OTP-4344)
  (Aux Id: Seq7375, (OTP-4317 see below))

- A bug which caused `memsup:get_system_memory_data()` to fail on linux/freebsd/win32 has been fixed.
  (Own Id: OTP-4489)

### Improvements and new features

- cpu_sup:util/0 and cpu_sup:util/1 which returns information about cpu utilization have been added. For further information see cpu_sup(3).
  (Own Id: OTP-4249)
  (Aux Id: Seq7278, Seq7332)

- Nodename is now used as key in loadtable (os_mon mib).
  (*** POTENTIAL INCOMPATIBILITY ***)
  (Own Id: OTP-4501)
  (Aux Id: seq7435, seq7549, seq7596)

- The loadCpuLoad5, loadCpuLoad15 values has been added to the os_mon mib.
  (Own Id: OTP-4502)
  (Aux Id: seq7435, seq7549, seq7596)

## Os_mon 1.5.0

### Fixed errors and malfunctions

- Gen_server calls to the memsup server of the os_mon application could fail due to slow responses from the memsup port program. The memory polling is now handled by a separate process making answers from memsup more or less instant.
  The disksup server of the os_mon application is modified so that it does not use os:cmd() on Unix systems.
  (Own Id: OTP-4000)
  (Aux Id: Seq5275)

### Improvements and new features

- Support for os_mon disksup, memsup and cpu_sup for Linux was added. Code was contributed by Miguel Barreiro Paz <enano@fi.udc.es>.
  (Own Id: OTP-3996)

## Os_mon 1.3.9

### Fixed Errors and Malfunctions

- A bug in the disksup service has been corrected, where `disk_almost_full` alarms were not cleared correctly but remained in `alarm_handler`.
  Own Id: OTP-3696
  Aux Id: seq4888

## Os_mon 1.3.7

### Fixed Errors and Malfunctions

- UNIX:`disksup:get_disk_data()` did occasionally fail to return any data about disk usage. Alarms about almost full disks would also not be generated. This has been corrected.
  Own Id: OTP-3116

## Os_mon 1.3.4

### Fixed Errors and Malfunctions

- Changed MAX-ACCESS for `diskDescr` in OTP-OS-MON-MIB from `not-accessible` to `read-only`.
  Own Id: OTP-2693

## Os_mon 1.3.3

### Fixed Errors and Malfunctions

- Failover of a loaded MIB did not work. When a MIB was loaded on one node and that node crashed, the failover of the MIB to a new node did not work.
  Own Id: OTP-2200
  Aux Id: seq 651, HA75679

### Improvements and New Features

- Events in the Windows NT event log can be imported into erlang with the generic module nteventlog.
  Own Id: OTP-1673

## Os_mon 1.3.2

### Fixed Errors and Malfunctions

- Failover of a loaded MIB did not work. When a MIB was loaded on one node and that node crashed, the failover of the MIB to a new node did not work.
  Own Id: OTP-2200
  Aux Id: seq 651, HA75679

## Os_mon 1.3.1

### Fixed Errors and Malfunctions

- Failover/takeover of the SNMP agent administering the MIB did not work, since the old implementation tried to delete a Mnesia table on a node which was not up and running (which always is the case at failover). Now the SNMP related Mnesia table is defined to have the `local_content` property.
  Own Id: OTP-2146
  Aux Id: seq1

## Os_mon 1.3

### Improvements and New Features

- The `disksup` and `memsup` parts of os_mon is now supported on the WIN32 platform.
  Own Id: OTP-1670, OTP-1671
- The `memsup` part of os_mon is now supported on the VxWorks platform.

### Fixed Errors and Malfunctions

- The problem that `disksup` sometimes could hang the entire node during startup is solved.
  Own Id: OTP-1658

### Incompatibilities with Os_mon 1.2

- The SNMP Mib OS-MON-MIB has changed its name to OTP-OS-MON-MIB.

## Os_mon 1.2

### Improvements and New Features

- Added the attribute `loadCpuLoad` in the SNMP MIB `OS-MON-MIB`, in the `loadTable`. It uses `cpu_sup` to fetch the load.
  Own Id: OTP-1190
  Aux Id: PH3-OTP-3:7
- Added new module `cpu_sup`. It supervises the CPU load in the operating system.
  Own Id: OTP-1191

## Os_mon 1.1.1

### Improvements and New Features

- Adapted new application resource file possibility, i.e. module version is not specified any longer.

## Os_mon 1.1

### Improvements and New Features

- Added `os_sup`, a solaris syslog facility.
- Added the OS-MON-MIB for SNMP monitoring of os_mon.
- Added functions for inspection of configuration parameters for `disksup` and `memsup`.

### Incompatibilities

- Changed the output format from `disksup:get_disk_data/0`.