Skip to main content


serial class SYS.History.WriteDaemon extends %Library.SerialObject

A class describing the metrics kept for the Write Daemon cycle history. The system keeps a list of the last 20 cycles.

This class is primarily used as an embedded object in the PerfData interval collection. But it may also be accessed directly using the "Sample" query as an API to the Write Daemon cycle history.

For details, see History Monitor.

Property Inventory

Method Inventory


property BufferRedirty as %Numeric;
Number of database buffers written during the cycle that were also written in the prior cycle.
Property methods: BufferRedirtyDisplayToLogical(), BufferRedirtyGet(), BufferRedirtyIsValid(), BufferRedirtyLogicalToDisplay(), BufferRedirtyNormalize(), BufferRedirtySet()
property BufferWrite as %Numeric;
Number of database buffers written during the cycle.
Property methods: BufferWriteDisplayToLogical(), BufferWriteGet(), BufferWriteIsValid(), BufferWriteLogicalToDisplay(), BufferWriteNormalize(), BufferWriteSet()
property CycleTime as %Numeric;
Time (in milliseconds) for the Write Daemon cycle to complete
Property methods: CycleTimeDisplayToLogical(), CycleTimeGet(), CycleTimeIsValid(), CycleTimeLogicalToDisplay(), CycleTimeNormalize(), CycleTimeSet()
property ProcInGlobal as %Numeric;
Number of processes actively holding global buffers at the start of the cycle.
Property methods: ProcInGlobalDisplayToLogical(), ProcInGlobalGet(), ProcInGlobalIsValid(), ProcInGlobalLogicalToDisplay(), ProcInGlobalNormalize(), ProcInGlobalSet()
property SizeWrite as %Numeric;
The size of database buffers (in KB) written during the cycle.
Property methods: SizeWriteDisplayToLogical(), SizeWriteGet(), SizeWriteIsValid(), SizeWriteLogicalToDisplay(), SizeWriteNormalize(), SizeWriteSet()
property Sleep as %Numeric;
Time (in milliseconds) that the Write Daemon was inactive before this cycle began
Property methods: SleepDisplayToLogical(), SleepGet(), SleepIsValid(), SleepLogicalToDisplay(), SleepNormalize(), SleepSet()
property StartTime as %TimeStamp;
Time that this Write Daemon cycle began
Property methods: StartTimeDisplayToLogical(), StartTimeGet(), StartTimeIsValid(), StartTimeLogicalToDisplay(), StartTimeNormalize(), StartTimeOdbcToLogical(), StartTimeSet()
property TempQueue as %Numeric;
Number of "in-memory" (i.e. IRISTemp) buffers used at the start of the cycle.
Property methods: TempQueueDisplayToLogical(), TempQueueGet(), TempQueueIsValid(), TempQueueLogicalToDisplay(), TempQueueNormalize(), TempQueueSet()
property TempWrite as %Numeric;
Number of "in-memory" buffers written during the cycle (typically none written).
Property methods: TempWriteDisplayToLogical(), TempWriteGet(), TempWriteIsValid(), TempWriteLogicalToDisplay(), TempWriteNormalize(), TempWriteSet()
property TimeStamp as %String;
Start time as UTC date/time stamp in $ZTS format
Property methods: TimeStampDisplayToLogical(), TimeStampGet(), TimeStampIsValid(), TimeStampLogicalToDisplay(), TimeStampLogicalToOdbc(), TimeStampNormalize(), TimeStampSet()
property WIJTime as %Numeric;
Time (in milliseconds) that the Write Daemon was writing the Write Image Journal (WIJ) file
Property methods: WIJTimeDisplayToLogical(), WIJTimeGet(), WIJTimeIsValid(), WIJTimeLogicalToDisplay(), WIJTimeNormalize(), WIJTimeSet()
property WriteTime as %Numeric;
Time (in milliseconds) that the Write Daemon was writing buffers to the database(s)
Property methods: WriteTimeDisplayToLogical(), WriteTimeGet(), WriteTimeIsValid(), WriteTimeLogicalToDisplay(), WriteTimeNormalize(), WriteTimeSet()


classmethod SetSummary(ByRef Function As %String, Period As %String) as %Status
Configure the summary methods for this class for either the Hourly or Daily summaries. This is a comma-delimited list of functions to use for the summary. The available functions are Average, Maximum (high-water mark), Minimum (lowest value), Standard Deviation, Median, and Total. These are abbreviated in the 'Function' argument as "Avg", "Max", "Min", StDev", Med", and "Tot". If nothing is specified, the default is "Avg,Max,StDev". You may also specify the string "None" for a summary period to disable that summary.

A null 'Function' argument will return the current summary setting in the 'Function' variable.

The 'Period' argument can be either "Hourly" or "Daily".


query Sample()
Selects StartTime As %TimeStamp, Sleep As %Integer, WIJTime As %Integer, WriteTime As %Integer, CycleTime As %Integer, SizeWrite As %Integer, BufferWrite As %Integer, TempQueue As %Integer, TempWrite As %Integer, ProcInGlobal As %Integer, Flags As %Integer, TimeStamp As %String, BufferRedirty As %Integer
Fetch current Write Daemon cycle history.

Inherited Members

Inherited Methods

FeedbackOpens in a new tab