Loupe - Log - Monitor - Resolve
Gibraltar.Monitor Namespace / LogWriteMode Enumeration

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    LogWriteMode Enumeration
    In This Topic
    Selects the performance trade-off for writing a given message to the log.
    Syntax
    'Declaration
     
    
    Public Enum LogWriteMode 
       Inherits System.Enum
    public enum LogWriteMode : System.Enum 
    Members
    MemberValueDescription
    Queued0Return after placing the message on the queue. (Normal operation)
    WaitForCommit1Don't return until the message has been committed to disk.
    Remarks

    This enum selects the preferred trade-off between run-time performance and diagnostic data persistence for an individual log message being issued. By default (in API calls which do not take an argument of this type) Gibraltar uses LogWriteMode.Queued under normal conditions but will automatically enforce a wait-for-commit mode under certain abnormal conditions or during normal application exit. The LogWriteMode.WaitForCommit setting allows the issuer of a log message to specifically request that the call not return until the log message has been committed to disk, instead of the normal queue-and-return behavior.

    Queued
    This setting indicates that the caller prefers to continue execution as soon as possible and only cares that the message be placed on the queue to be eventually written into the log file on disk. Messages written with this mode could be lost if the application crashes and Gibraltar is not able to flush its queue to the log file on disk. Under certain unusual conditions and during normal application exit, even calls with this explicit setting may be forced to behave as WaitForCommit to provide better logging integrity in those scenarios.

    WaitForCommit
    This setting indicates that the caller needs to make sure this message makes it into the log file on disk because the application is exiting or may crash when it continues. The call will force a flush of the queue and block until Gibraltar has committed the message to the log file on disk. Messages written with this mode will not be lost--IF the call completes and returns--but will incur a significant performance hit, so it should generally only be used for critical information which needs to survive a crash scenario to help diagnose the cause of the crash.

    WaitForCommit mode still can not guarantee that the log message will make it to disk in pathological cases, but it designates this as a higher priority than performance for an individual log message for scenarios where the persistence of this information is expected to be important in diagnosing a condition which might prevent normal Queued messages from making it to disk--for example, when the caller will be causing the application to exit abruptly upon return and needs the log to reflect the reason why.

    Inheritance Hierarchy

    System.Object
       System.ValueType
          System.Enum
             Gibraltar.Monitor.LogWriteMode

    Requirements

    Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

    See Also