com.bigdata.counters.linux

Class SysstatUtil

java.lang.Object

com.bigdata.counters.linux.SysstatUtil

public class SysstatUtil
extends Object

Some utility methods related to integration with sysstat.

Version:

$Id$

Author:

Bryan Thompson

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	SysstatUtil.Options

Constructor Summary

Constructors

Constructor and Description
SysstatUtil()

Method Summary

Methods

Modifier and Type	Method and Description
static Map<String,String>	getDataMap(String header, String data) Takes header and data lines and generates a Map from them
static File	getPath(String cmd) Returns the path to the specified sysstat utility (pidstat, sar, etc).
static DateFormat	newDateFormat() Deprecated. sysstat only reports the TIME OF DAY. In order to get the UTC time it has to be corrected by the UTC time of the start of the current day. Since very little latency is expected between the report by sysstat of its performance counters and the parsing of those performance counters by our code, it is MUCH easier and more robust to simply use the current time as reported by System.currentTimeMillis().
static String[]	splitDataLine(String data) Splits a data line into fields based on whitespace and skipping over the date field (index zero (0) is the index of the first non-date field).

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SysstatUtil

public SysstatUtil()

Method Detail

getPath

public static final File getPath(String cmd)

Returns the path to the specified sysstat utility (pidstat, sar, etc). The default is directory is . This may be overridden using the property. The following directories are also searched if the program is not found in the configured default location:

• /usr/bin
• /usr/local/bin

Returns:

The path to the specified utility. If the utility was not found, then the configured path to the utility will be returned anyway.

splitDataLine

public static String[] splitDataLine(String data)

Splits a data line into fields based on whitespace and skipping over the date field (index zero (0) is the index of the first non-date field).

Note: Some fields can overflow, e.g., RSS. When this happens the fields in the data lines wind up eating into the whitespace to their right. This means that it is more robust to split the lines based on whitespace once we have skipped over the date field. Since we specify using PIDStatCollector.setEnvironment(Map) that we want an ISO date format, we know that the date field is 11 characters. The data lines are broken up by whitespace after that.

Note: Since we split on whitespace, the resulting strings are already trimmed.

Returns:

The fields.

getDataMap

public static Map<String,String> getDataMap(String header,
                            String data)

Takes header and data lines and generates a Map from them

Returns:

a Map where keys are fields names and values are fields values.

newDateFormat

public static DateFormat newDateFormat()

Deprecated. sysstat only reports the TIME OF DAY. In order to get the UTC time it has to be corrected by the UTC time of the start of the current day. Since very little latency is expected between the report by sysstat of its performance counters and the parsing of those performance counters by our code, it is MUCH easier and more robust to simply use the current time as reported by System.currentTimeMillis().

Used to parse the timestamp associated with each row of sysstat output.

Note: This assumes that you have controlled the date format using the sysstat ISO date option.

Note: This is not thread-safe - use a distinct instance for each PIDStatCollector or SarCpuUtilizationCollector.