Transactions
For more information about transaction, see the following. For example, see the following on the transaction analysis guide in case of using the hitmap.
Transaction Tracing
While the transaction performance means the summary metrics or attributes between the start and end of transaction, the transaction profile traces the steps during transactions. If any transaction is slow or erroneous, the execution records must be traced step by step to find the cause. This is called transaction tracing.
The types of steps that WhaTap collects include SQL steps, HTTP call steps, message steps, socket open steps, DB connection steps, and method steps.
WhaTap's step is used with the same meaning as Span.
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DB connection step START-END
It includes the performance for connection to RDB. Step information includes the name, response time, and error.
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SQL Step START-END
It includes the performance for JDBC SQL. Step information includes connection data, SQL statements, and errors.
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HTTP Call step START-END
It includes the performance for the outbound HTTP service calls. Step information includes URL, host, port, response time, and errors.
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Message step ADD
While collecting traces, the message steps are used to collect the records of all irregular sections.
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SOCKET Step ADD
Step to represent the socket open.
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METHOD Step START-END
The method response time is traced.
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ACTIVE STACK Step START-END
It includes the active stack information. It is created and collected by a separate thread and it is added to the transaction trace.
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profile_step_normal_count Int
Default
1000
Set the default step count for tracing transactions.
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profile_step_heavy_count Int
Default
1020
If the trace's default step count is exceeded, it limits the maximum heavy step count. In
profile_step_normal_count
, it counts the steps that are overprofile_step_heavy_time
. The steps with no response time are not collected. -
profile_step_max_count Int
Default
1024
Set the maximum number of trace steps. If the number of collected trace steps exceeds this value, all steps collected later are ignored. If
profile_step_heavy_count
is set up to 1000, active stacks are collected as many asprofile_step_max_count
. -
profile_step_heavy_time MiliSecond
Default
100
Set the criterion of heavy steps. If the execution time is greater than the set value and
profile_step_normal_count
is exceeded, recording is made withinprofile_step_heavy_count
. -
profile_basetime MiliSecond
Default
500
Transaction trace data is not collected if a transaction is terminated within the set value. The first URL called in every 5 minutes and the erroneous profile data are collected.
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query_string_enabled Boolean
Default
false
It enables the function to collect query strings for transaction URLs.
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query_string_urls String
It registers the URLs to collect query strings for transactions. To register multiple items, comma (,) is used as the delimiter.
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hook_method_patterns String
Use this when measuring the response time of a specific method. Use the values in the
[MODULE_NAME]:[CLASS_NAME].[FUNCTION_NAME]
or[MODULE_NAME]:[FUNCTION_NAME]
format. Multiple method patterns can be set using comma (,) as the delimiter. All classes for a module or all modules for a class can be traced using asterisk (*).Note-
The methods registered through this option can be checked through the Method step in Hitmap, Trace analysis, or Transaction information window.
-
Because tracing all modules may incur overhead, it is recommended to use accurate module and method names if possible.
-
-
trace_error_callstack_depth Int
Default
50
Set the maximum number of call stack lines when collecting error call stacks for transactions. This data can be viewed from the error statistical data.
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trace_active_callstack_depth Int
Default
50
Set the maximum number of call stack lines when collecting active stacks for transactions.
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trace_active_transaction_slow_time MiliSecond
Default
3000
Set the response criteria in the slow section of the active transaction's arc equalizer.
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trace_active_transaction_very_slow_time MiliSecond
Default
8000
Set the response criteria in the very slow section of the active transaction's arc equalizer.
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trace_active_transaction_lost_time MiliSecond
Default
300000
Timeout waiting for a transaction to end. If a transaction does not end within 5 minutes, no further transaction data is collected.
HTTP transaction tracing
The following agent options trace and record various data related to HTTP requests and responses. This allows you to closely monitor and analyze the HTTP transactions for applications. You can add parameter values to the transaction names or exclude specific URLs or HTTP methods. You can also record transactions in detail, including HTTP headers and parameters.
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profile_http_header_enabled Boolean
Default
false
The HTTP header's content is output in the transaction trace. This setting is used to expose headers to the transaction trace regardless of whether headers are collected or not.
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profile_http_parameter_enabled Boolean
Default
false
Set it to
true
to record HTTP parameters in the trace history. However, the parameters can be retrieved only by entering a separate security key. Set the security key to 6 digits in paramkey.txt of the agent installation path. If paramkey.txt does not exist, it is automatically generated and a random key is set. -
trace_normalize_enabled Boolean
Default
true
It enables the function to parse and normalize transaction URLs.
NoteIf the value is changed to
false
, it disables the path parameter parsing. In this case, it is recommended to temporarily use the setting only for debugging purposes because the statistical data is less meaningful. -
trace_auto_normalize_enabled(*) Boolean
Default
true
It enables automatic parsing of pattern values by extracting them from annotations when normalizing transaction URLs.
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trace_normalize_urls String
The transaction URLs are parsed and normalized. It deletes the path parameters by parsing the call URL patterns.
NoteFor example, if declared as
/a/{v}/b
,a/123/b
is replaced bya/{v}/b
. For multiple values, use comma (,) as the delimiter. Using/a/*/b
, you can collect after deleting the path parameter with a specific format. -
web_static_content_extensions(*) String
Default
js, htm, html, gif, png, jpg, css, swf, ico
Specify the extension to determine the static content. Transactions with extensions set here are excluded from transaction tracing and counting.
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trace_ignore_url_set String
It sets URLs to exclude from transaction tracing. For multiple values, use comma (,) as the delimiter.
NoteThe URLs registered through this option are excluded from the Hitmap, Trace analysis, or Transaction information window for collection.
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trace_ignore_url_prefix String
Set the URL prefix for excluding transactions during collection. Any URLs whose prefix matches the set value do not collect the transaction performance.
NoteThe URLs registered through this option are excluded from the Hitmap, Trace analysis, or Transaction information window for collection.
Non-HTTP transaction tracing
-
Transaction end point
The end point is the start method of the transaction. In case of the HTTP transaction,
HttpServlet.service()
orFilter.doFilter()
is the start point of transaction, and this point is called "transaction end point." -
Non-HTTP tracing
The performance from the start to the end of the method specified as the transaction end point, is called "transaction performance." To trace non HTTP transactions, be sure to specify the end point.
NoteFinding the end point
- Set the transaction trace for all methods where transactions are supposed to be called.
- After restarting, trigger a transaction for monitoring.
- Turn on the
back stack
option to pinpoint the entry method.
Selecting the target
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Method Trace Setting
Set the method trace. Be sure to specify a class that is called in transactions. The JDBC driver is useful for the programs that use the database.
whatap.confhook_method_patterns=jdbc.*.*
hook_method_access_public_enabled=true
hook_method_access_protected_enabled=true
hook_method_access_none_enabled=true -
Transaction start option setting
Start a transaction when the method is called. Turn on the transaction start option and the option to dump the stack at the start of a transaction.
whatap.conftrace_auto_transaction_enabled=true
trace_auto_transaction_backstack_enabled=true -
Trace analysis after restart
Restart it. After calling the service, you can see the transaction being traced.
If you view the transaction, you can see that the methods of all classes starting with
jdbc.*
appear in this transaction. If you view the transaction trace, you can see the message step called TRANSACTION BACKSTACK.TRANSACTION BACKSTACKjdbc.FakePreparedStatement.executeQuery(FakePreparedStatement.java),
com.virtual.dao.SelectDAO.execute2(SelectDAO.java:29),
com.virtual.web.SimulaNonHttp.execute(SimulaNonHttp.java:147),
com.virtual.web.SimulaNonHttp.process(SimulaNonHttp.java:76),
com.virtual.web.SimulaNonHttp.run(SimulaNonHttp.java:100) -
Check Stack Content
By checking the stack content, you can infer which method the transaction is departing from.
Examplecom.virtual.web.SimulaNonHttp.execute(SimulaNonHttp.java:147),
com.virtual.web.SimulaNonHttp.process(SimulaNonHttp.java:76),
com.virtual.web.SimulaNonHttp.run(SimulaNonHttp.java:100)One of the above three methods can be determined as the start point of a transaction. In this situation, perform reverse compilation to determine the appropriate transaction end point.
Looking at the logic,
while()
runs withinSimulaNonHttp.run
,SimulaNonHttp.process()
is called, and thenSimulaNonHttp.execute()
is run. We can guess thatprocess()
is appropriate. This part must be determined by looking at the source.TipThe most important criterion for end point is that it must be ended. Under normal circumstances, it must terminate immediately without any delay so that the performance evaluation can be made.
Setting the end point of transaction
-
Set the transaction start point as follows:
whatap.confhook_service_patterns=com.virtual.web.SimulaNonHttp.process
-
Restart the application.
The process()
method becomes the end point of a new transaction.
For the hook_service_patterns
option, wildcard characters cannot be used. To set multiple values, use comma (,) as the delimiter.
Defining the transaction name
Generally, transactions are identified by the method name.
service_name_mode=[full,class,method,string,arg]
service_name_index=0
-
service_name_mode
You can specify any of 5 options:
full
,class
,method
,string
, andarg
.-
full
: The full class name is used as the service name. -
class
: The class name is used as the service name. -
method
: The method name is used as the service name. -
string
: The first parameter in the text string is used as the service name. -
arg
: Among parameters, the parameter of the index specified in theservice_name_index
option is used as the service name.
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Multiple transaction trace
The following options are used to trace and monitor cross-application calls. The options can help you understand the interactions between multiple applications. Various options provided allow you to fine-tune the behaviors for tracing multiple transactions.
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mtrace_rate Percentage
Default
0
This option sets the rate of the MTID (Multi Transaction ID) issued when the first transaction occurs. By tracing MTIDs, the calls between all registered applications can be checked. Through the Caller & Callee function, the transaction trace can be viewed for the applications that belong to the same project.
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mtrace_spec String
Default:
v1
Set the application version of the current instance. You can arbitrarily set a string. This data is used for call statistics.
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mtrace_send_url_length Integer
Default
80
The HTTP caller passes its URL to callees. At this time, the URL length is restricted. This sets the length value.