module Database.RRDtool
- ( DataSource(..)
- , Expr(..)
- , createRRD
+ ( module Database.RRDtool.Create
)
where
-import Data.Time.Clock
-import Data.Time.Clock.POSIX
-
-
--- |A single RRD can accept input from several data sources (DS), for
--- example incoming and outgoing traffic on a specific communication
--- line. With the DS configuration option you must define some basic
--- properties of each data source you want to store in the RRD.
---
--- /NOTE on COUNTER vs DERIVE/
---
--- by Don Baarda <don.baarda@baesystems.com>
---
--- If you cannot tolerate ever mistaking the occasional counter reset
--- for a legitimate counter wrap, and would prefer \"Unknowns\" for
--- all legitimate counter wraps and resets, always use DERIVE with
--- @'dsMin' = 0@. Otherwise, using COUNTER with a suitable max will
--- return correct values for all legitimate counter wraps, mark some
--- counter resets as \"Unknown\", but can mistake some counter resets
--- for a legitimate counter wrap.
---
--- For a 5 minute step and 32-bit counter, the probability of
--- mistaking a counter reset for a legitimate wrap is arguably about
--- 0.8% per 1Mbps of maximum bandwidth. Note that this equates to 80%
--- for 100Mbps interfaces, so for high bandwidth interfaces and a
--- 32bit counter, DERIVE with @'dsMin' = 0@ is probably preferable. If
--- you are using a 64bit counter, just about any max setting will
--- eliminate the possibility of mistaking a reset for a counter wrap.
-data DataSource
- = -- |GAUGE is for things like temperatures or number of people in
- -- a room or the value of a RedHat share.
- GAUGE {
- -- |The name you will use to reference this particular data
- -- source from an RRD. A ds-name must be 1 to 19 characters
- -- long in the characters @[a-zA-Z0-9_]@.
- dsName :: !String
- -- |Defines the maximum number of seconds that may
- -- pass between two updates of this data source before the
- -- value of the data source is assumed to be @*UNKNOWN*@.
- , dsHeartbeat :: !NominalDiffTime
- -- |'dsMin' and 'dsMax' Define the expected range values for
- -- data supplied by a data source. If 'dsMin' and\/or 'dsMax'
- -- any value outside the defined range will be regarded as
- -- @*UNKNOWN*@. If you do not know or care about 'dsMin' and
- -- 'dsMax', set them to 'Nothing' for unknown. Note that
- -- 'dsMin' and 'dsMax' always refer to the processed values of
- -- the DS. For a traffic-'COUNTER' type DS this would be the
- -- maximum and minimum data-rate expected from the device.
- --
- -- If information on minimal\/maximal expected values is
- -- available, always set the min and\/or max properties. This
- -- will help RRDtool in doing a simple sanity check on the
- -- data supplied when running update.
- , dsMin :: !(Maybe Double)
- -- |See 'dsMin'.
- , dsMax :: !(Maybe Double)
- }
- -- |COUNTER is for continuous incrementing counters like the
- -- ifInOctets counter in a router. The COUNTER data source
- -- assumes that the counter never decreases, except when a
- -- counter overflows. The update function takes the overflow
- -- into account. The counter is stored as a per-second
- -- rate. When the counter overflows, RRDtool checks if the
- -- overflow happened at the 32bit or 64bit border and acts
- -- accordingly by adding an appropriate value to the result.
- | COUNTER {
- dsName :: !String
- , dsHeartbeat :: !NominalDiffTime
- , dsMin :: !(Maybe Double)
- , dsMax :: !(Maybe Double)
- }
- -- |DERIVE will store the derivative of the line going from the
- -- last to the current value of the data source. This can be
- -- useful for gauges, for example, to measure the rate of people
- -- entering or leaving a room. Internally, derive works exactly
- -- like COUNTER but without overflow checks. So if your counter
- -- does not reset at 32 or 64 bit you might want to use DERIVE
- -- and combine it with a 'dsMin' value of 0.
- | DERIVE {
- dsName :: !String
- , dsHeartbeat :: !NominalDiffTime
- , dsMin :: !(Maybe Double)
- , dsMax :: !(Maybe Double)
- }
- -- |ABSOLUTE is for counters which get reset upon reading. This
- -- is used for fast counters which tend to overflow. So instead
- -- of reading them normally you reset them after every read to
- -- make sure you have a maximum time available before the next
- -- overflow. Another usage is for things you count like number
- -- of messages since the last update.
- | ABSOLUTE {
- dsName :: !String
- , dsHeartbeat :: !NominalDiffTime
- , dsMin :: !(Maybe Double)
- , dsMax :: !(Maybe Double)
- }
- -- |COMPUTE is for storing the result of a formula applied to
- -- other data sources in the RRD. This data source is not
- -- supplied a value on update, but rather its Primary Data
- -- Points (PDPs) are computed from the PDPs of the data sources
- -- according to the rpn-expression that defines the
- -- formula. Consolidation functions are then applied normally to
- -- the PDPs of the COMPUTE data source (that is the
- -- rpn-expression is only applied to generate PDPs). In database
- -- software, such data sets are referred to as \"virtual\" or
- -- \"computed\" columns.
- --
- -- FIXME: doc links
- | COMPUTE {
- dsName :: !String
- -- |rpn-expression defines the formula used to compute the PDPs
- -- of a COMPUTE data source from other data sources in the same
- -- \<RRD\>. It is similar to defining a CDEF argument for the
- -- graph command. For COMPUTE data sources, the following RPN
- -- operations are not supported: COUNT, PREV, TIME, and
- -- LTIME. In addition, in defining the RPN expression, the
- -- COMPUTE data source may only refer to the names of data
- -- source listed previously in the create command. This is
- -- similar to the restriction that CDEFs must refer only to DEFs
- -- and CDEFs previously defined in the same graph command.
- --
- -- FIXME: doc links
- , dsExpr :: !Expr
- }
- deriving (Eq, Ord, Show)
-
-data Expr
- = UNK
- deriving (Show, Eq, Ord)
-
--- |The 'createRRD' function lets you set up new Round Robin Database
--- (RRD) files. The file is created at its final, full size and filled
--- with @*UNKNOWN*@ data.
-createRRD
- :: FilePath -- ^The name of the RRD you want to create. RRD files
- -- should end with the extension @.rrd@. However,
- -- RRDtool will accept any filename.
- -> Bool -- ^Do not clobber an existing file of the same name.
- -> Maybe POSIXTime -- ^Specifies the time in seconds since
- -- @1970-01-01 UTC@ when the first value should
- -- be added to the RRD. RRDtool will not accept
- -- any data timed before or at the time
- -- specified. (default: @now - 10s@)
- -> Maybe NominalDiffTime -- ^Specifies the base interval in
- -- seconds with which data will be fed
- -- into the RRD. (default: 300 sec)
- -> [DataSource] -- ^Data sources to accept input from.
- -> IO ()
-createRRD = error "FIXME"
\ No newline at end of file
+import Database.RRDtool.Create
projects / hs-rrdtool.git / blobdiff