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   pmlogrewrite    ( 1 )

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REWRITING RULES SYNTAX

A configuration file contains zero or more rewriting rules as defined below.

Keywords and special punctuation characters are shown below in bolditalic font and are case-insensitive, so METRIC, metric and Metric are all equivalent in rewriting rules.

The character ``#'' introduces a comment and the remainder of the line is ignored. Otherwise the input is relatively free format with optional white space (spaces, tabs or newlines) between lexical items in the rules.

A global rewriting rule has the form:

GLOBAL { globalspec ... }

where globalspec is zero or more of the following clauses:

HOSTNAME -> hostname

Modifies the label records in the outlog PCP archive, so that the metrics will appear to have been collected from the host hostname.

TIME -> delta

Both metric values and the instance domain metadata in a PCP archive carry timestamps. This clause forces all the timestamps to be adjusted by delta, where delta is an optional sign ``+'' (the default) or ``-'', an optional number of hours followed by a colon ``:'', an optional number of minutes followed by a colon ``:'', a number of seconds, an optional fraction of seconds following a period ``.''. The simplest example would be ``30'' to increase the timestamps by 30 seconds. A more complex example would be ``-23:59:59.999'' to move the timestamps backwards by one millisecond less than one day.

TZ -> "timezone"

Modifies the label records in the outlog PCP archive, so that the metrics will appear to have been collected from a host with a local timezone of timezone. timezone must be enclosed in quotes, and should conform to the valid timezone syntax rules for the local platform.

An indom rewriting rule modifies an instance domain and has the form:

INDOM domain.serial { indomspec ... }

where domain and serial identify one or more existing instance domains from inlog - typically domain would be an integer in the range 1 to 510 and serial would be an integer in the range 0 to 4194304.

As a special case serial could be an asterisk ``*'' which means the rule applies to every instance domain with a domain number of domain.

If a designated instance domain is not in inlog the rule has no effect.

The indomspec is zero or more of the following clauses:

INAME "oldname" -> "newname"

The instance identified by the external instance name oldname is renamed to newname. Both oldname and newname must be enclosed in quotes.

As a special case, the new name may be the keyword DELETE (with no quotes), and then the instance oldname will be expunged from outlog which removes it from the instance domain metadata and removes all values of this instance for all the associated metrics.

If the instance names contain any embedded spaces then special care needs to be taken in respect of the PCP instance naming rule that treats the leading non-space part of the instance name as the unique portion of the name for the purposes of matching and ensuring uniqueness within an instance domain, refer to pmdaInstance(3) for a discussion of this issue.

As an illustration, consider the hypothetical instance domain for a metric which contains 2 instances with the following names: red eek urk

Then some possible INAME clauses might be:

"eek" -> "yellow like a flower" Acceptable, oldname "eek" matches the "eek urk" instance.

"red" -> "eek" Error, newname "eek" matches the existing "eek urk" instance.

"eek urk" -> "red of another hue" Error, newname "red of another hue" matches the existing "red" instance.

INDOM -> newdomain.newserial

Modifies the metadata for the instance domain and every metric associated with the instance domain. As a special case, newserial could be an asterisk ``*'' which means use serial from the indom rewriting rule, although this is most useful when serial is also an asterisk. So for example: indom 29.* { indom -> 109.* } will move all instance domains from domain 29 to domain 109.

INDOM -> DUPLICATE newdomain.newserial

A special case of the previous INDOM clause where the instance domain is a duplicate copy of the domain.serial instance domain from the indom rewriting rule, and then any mapping rules are applied to the copied newdomain.newserial instance domain. This is useful when a PMDA is split and the same instance domain needs to be replicated for domain domain and domain newdomain. So for example if the metrics foo.one and foo.two are both defined over instance domain 12.34, and foo.two is moved to another PMDA using domain 27, then the following rewriting rules could be used: indom 12.34 { indom -> duplicate 27.34 } metric foo.two { indom -> 27.34 pmid -> 27.*.* }

INST oldid -> newid

The instance identified by the internal instance identifier oldid is renumbered to newid. Both oldid and newid are integers in the range 0 to 231-1.

As a special case, newid may be the keyword DELETE and then the instance oldid will be expunged from outlog which removes it from the instance domain metadata and removes all values of this instance for all the associated metrics.

A metric rewriting rule has the form:

METRIC metricid { metricspec ... }

where metricid identifies one or more existing metrics from inlog using either a metric name, or the internal encoding for a metric's PMID as domain.cluster.item. In the latter case, typically domain would be an integer in the range 1 to 510, cluster would be an integer in the range 0 to 4095, and item would be an integer in the range 0 to 1023.

As special cases item could be an asterisk ``*'' which means the rule applies to every metric with a domain number of domain and a cluster number of cluster, or cluster could be an asterisk which means the rule applies to every metric with a domain number of domain and an item number of item, or both cluster and item could be asterisks, and rule applies to every metric with a domain number of domain.

If a designated metric is not in inlog the rule has no effect.

The metricspec is zero or more of the following clauses:

DELETE

The metric is completely removed from outlog, both the metadata and all values in results are expunged.

INDOM -> newdomain.newserial [ pick ]

Modifies the metadata to change the instance domain for this metric. The new instance domain must exist in outlog.

The optional pick clause may be used to select one input value, or compute an aggregate value from the instances in an input result, or assign an internal instance identifier to a single output value. If no pick clause is specified, the default behaviour is to copy all input values from each input result to an output result, however if the input instance domain is singular (indom PM_INDOM_NULL) then the one output value must be assigned an internal instance identifier, which is 0 by default, unless over-ridden by a INST or INAME clause as defined below.

The choices for pick are as follows:

OUTPUT FIRST choose the value of the first instance from each input result

OUTPUT LAST choose the value of the last instance from each input result

OUTPUT INST instid choose the value of the instance with internal instance identifier instid from each result; the sequence of rewriting rules ensures the OUTPUT processing happens before instance identifier renumbering from any associated indom rule, so instid should be one of the internal instance identifiers that appears in inlog

OUTPUT INAME "name" choose the value of the instance with name for its external instance name from each result; the sequence of rewriting rules ensures the OUTPUT processing happens before instance renaming from any associated indom rule, so name should be one of the external instance names that appears in inlog

OUTPUT MIN choose the smallest value in each result (metric type must be numeric and output instance will be 0 for a non-singular instance domain)

OUTPUT MAX choose the largest value in each result (metric type must be numeric and output instance will be 0 for a non-singular instance domain)

OUTPUT SUM choose the sum of all values in each result (metric type must be numeric and output instance will be 0 for a non-singular instance domain)

OUTPUT AVG choose the average of all values in each result (metric type must be numeric and output instance will be 0 for a non-singular instance domain)

If the input instance domain is singular (indom PM_INDOM_NULL) then independent of any pick specifications, there is at most one value in each input result and so FIRST, LAST, MIN, MAX, SUM and AVG are all equivalent and the output instance identifier will be 0.

In general it is an error to specify a rewriting action for the same metadata or result values more than once, e.g. more than one INDOM clause for the same instance domain. The one exception is the possible interaction between the INDOM clauses in the indom and metric rules. For example the metric sample.bin is defined over the instance domain 29.2 in inlog and the following is acceptable (albeit redundant): indom 29.* { indom -> 109.* } metric sample.bin { indom -> 109.2 } However the following is an error, because the instance domain for sample.bin has two conflicting definitions: indom 29.* { indom -> 109.* } metric sample.bin { indom -> 123.2 }

INDOM -> NULL[ pick ]

The metric (which must have been previously defined over an instance domain) is being modified to be a singular metric. This involves a metadata change and collapsing all results for this metric so that multiple values become one value.

The optional pick part of the clause defines how the one value for each result should be calculated and follows the same rules as described for the non-NULL INDOM case above.

In the absence of pick, the default is OUTPUT FIRST.

NAME -> newname

Renames the metric in the PCP archive's metadata that supports the Performance Metrics Name Space (PMNS). newname should not match any existing name in the archive's PMNS and must follow the syntactic rules for valid metric names as outlined in PMNS(5).

PMID -> newdomain.newcluster.newitem

Modifies the metadata and results to renumber the metric's PMID. As special cases, newcluster could be an asterisk ``*'' which means use cluster from the metric rewriting rule and/or item could be an asterisk which means use item from the metric rewriting rule. This is most useful when cluster and/or item is also an asterisk. So for example: metric 30.*.* { pmid -> 123.*.* } will move all metrics from domain 30 to domain 123.

SEM -> newsem

Change the semantics of the metric. newsem should be the XXX part of the name of one of the PM_SEM_XXX macros defined in <pcp/pmapi.h> or pmLookupDesc(3), e.g. COUNTER for PM_TYPE_COUNTER.

No data value rewriting is performed as a result of the SEM clause, so the usefulness is limited to cases where a version of the associated PMDA was exporting incorrect semantics for the metric. pmlogreduce(1) may provide an alternative in cases where re-computation of result values is desired.

TYPE -> newtype

Change the type of the metric which alters the metadata and may change the encoding of values in results. newtype should be the XXX part of the name of one of the PM_TYPE_XXX macros defined in <pcp/pmapi.h> or pmLookupDesc(3), e.g. FLOAT for PM_TYPE_FLOAT.

Type conversion is only supported for cases where the old and new metric type is numeric, so PM_TYPE_STRING, PM_TYPE_AGGREGATE and PM_TYPE_EVENT are not allowed. Even for the numeric cases, some conversions may produce run-time errors, e.g. integer overflow, or attempting to rewrite a negative value into an unsigned type.

TYPE IF oldtype -> newtype

The same as the preceding TYPE clause, except the type of the metric is only changed to newtype if the type of the metric in inlog is oldtype.

This useful in cases where the type of metricid in inlog may be platform dependent and so more than one type rewriting rule is required.

UNITS -> newunits [ RESCALE ]

newunits is six values separated by commas. The first 3 values describe the dimension of the metric along the dimensions of space, time and count; these are integer values, usually 0, 1 or -1. The remaining 3 values describe the scale of the metric's values in the dimensions of space, time and count. Space scale values should be 0 (if the space dimension is 0), else the XXX part of the name of one of the PM_SPACE_XXX macros, e.g. KBYTE for PM_TYPE_KBYTE. Time scale values should be 0 (if the time dimension is 0), else the XXX part of the name of one of the PM_TIME_XXX macros, e.g. SEC for PM_TIME_SEC. Count scale values should be 0 (if the time dimension is 0), else ONE for PM_COUNT_ONE.

The PM_SPACE_XXX, PM_TIME_XXX and PM_COUNT_XXX macros are defined in <pcp/pmapi.h> or pmLookupDesc(3).

When the scale is changed (but the dimension is unaltered) the optional keyword RESCALE may be used to chose value rescaling as per the -s command line option, but applied to just this metric.

When changing the domain number for a metric or instance domain, the new domain number will usually match an existing PMDA's domain number. If this is not the case, then the new domain number should not be randomly chosen; consult $PCP_VAR_DIR/pmns/stdpmid for domain numbers that are already assigned to PMDAs.

A text rewriting rule modifies a help text record and has the form:

TEXT textid [ texttype ] [ "textcontent" ] { textspec ... }

where textid identifies the metric or instance domain with which the text is currently associated, and is either METRIC metricid or INDOM domain.serial.

metricid has the same form and meaning as for a METRIC rewriting rule (see above) and domain.serial has the same form and meaning as for an INDOM rewriting rule (see above).

The optional texttype identifies the type of text and may be one of ONELINE to select the one line help text, HELP to select the full help text, or ALL or an asterisk ``*'' to select both types of help text. If texttype is not specified, then the default is ONELINE.

The optional textcontent further restricts the selected text records to those containing the specified content. Characters such as double quotes may be escaped by preceding them with a backslash ``\''.

If a designated help text record is not in inlog the rule has no effect.

The textspec is zero or more of the following clauses:

DELETE

The selected text is completely removed from outlog.

INDOM -> newdomain.newserial

Reassociates the text with the specified instance domain. As a special case, newserial could be an asterisk ``*'' which means use serial from the text rewriting rule, although this is most useful when serial is also an asterisk. So for example: text indom 29.* all { indom -> 109.* } will reassociate all text associated with instance domains from domain 29 to domain 109.

METRIC -> newdomain.newcluster.newitem

Reassociates the text with the specified metric. As special cases, newcluster could be an asterisk ``*'' which means use cluster from the text rewriting rule and/or item could be an asterisk which means use item from the text rewriting rule. This is most useful when cluster and/or item is also an asterisk. So for example: text metric 30.*.* all { metric -> 123.*.* } will reassociate all text associated with metrics from domain 30 to domain 123.

TEXT -> "new-text"

Replaces the content of the selected text with new-text.

A label rewriting rule modifies a label record and has the form:

LABEL labelid [ instance ] [ "label-name" ] [ "label-value" ] { labelspec ... }

where labelid refers to the global context or identifies the metric domain, metric cluster, metric item, instance domain, or instance domain instances with which the label is currently associated, and is either CONTEXT or DOMAIN domainid or CLUSTER domainid.clusterid or ITEM metricid or INDOM domain.serial or INSTANCES domain.serial.

metricid has the same form and meaning as for a METRIC rewriting rule (see above). clusterid may be an asterisk ``*'' which means the rule applies to every metric with a domain number of domainid in the same way as an asterisk may be used for the cluster within metricid.

domain.serial has the same form and meaning as for an INDOM rewriting rule (see above).

In the case of an INSTANCES labelid, the name or number of a specific instance may be optionally specified as instance. This name or number number may be omitted or specified as an asterisk ``*'' to indicate that labels for all instances of the specified instance domain are selected. If an instance name is specified, it must be within double quotes. If the instance name contains any embedded spaces then special care needs to be taken in respect of the PCP instance naming rule that treats the leading non-space part of the instance name as the unique portion of the name for the purposes of matching and ensuring uniqueness within an instance domain, refer to pmdaInstance(3) for a discussion of this issue.

In all cases, a "label-name" and/or a "label-value" may be optionally specified in double quotes in order to select labels with the given name and/or given value. These may individually be omitted or specified as asterisks ``*'' to indicate that labels with all names and/or values are selected.

If a designated label record is not in inlog the rule has no effect.

The labelspec is zero or more of the following clauses:

DELETE

The selected labels are completely removed from outlog.

NEW "new-label-name" "new-label-value"

A new label with the name "new-label-name" and the value "new-label-value" is created and associated with the specified labelid and optional instance (in the case of a INSTANCES labelid). If "label-name" or "label-value" were specified, then they are ignored with a warning. If instance is not specified for an INSTANCES labelid, then a new label will be created for each instance in the specified instance domain.

LABEL -> "new-label-name"

The name of the selected label(s) is changed to "new- label-name".

VALUE -> "new-label-value"

The value of the selected label(s) is changed to "new- label-value".

DOMAIN -> newdomain

Reassociates the selected label(s) with the specified metric domain. For example: label domain 30 { domain -> 123 } will reassociate all labels associated with domains from domain 30 to domain 123.

CLUSTER -> newdomain.newcluster

Reassociates the selected label(s) with the specified metric cluster. As a special case, newcluster could be an asterisk ``*'' which means use cluster from the label rewriting rule. This is most useful when cluster is also an asterisk. So for example: label cluster 30.* { cluster -> 123.* } will reassociate all labels associated with clusters from domain 30 to domain 123.

ITEM -> newdomain.newcluster.newitem

Reassociates the selected label(s) with the specified metric item. As special cases, newcluster could be an asterisk ``*'' which means use cluster from the label rewriting rule and/or item could be an asterisk which means use item from the label rewriting rule. This is most useful when cluster and/or item is also an asterisk. So for example: label item 30.*.* { item -> 123.*.* } will reassociate all labels associated with metrics from domain 30 to domain 123.

INDOM -> newdomain.newserial

Reassociates the selected label(s) with the specified instance domain. As a special case, newserial could be an asterisk ``*'' which means use serial from the label rewriting rule, although this is most useful when serial is also an asterisk. So for example: label indom 29.* { indom -> 109.* } will reassociate all labels associated with instance domains from domain 29 to domain 109.

INSTANCES -> newdomain.newserial

This is the same as INDOM except that it reassociates the selected label(s) with the instances of the specified instance domain.