Package com.vaadin.open

Class LinuxProcFileReader

java.lang.Object
com.vaadin.open.LinuxProcFileReader
public class LinuxProcFileReader extends Object
Linux /proc file reader. Read tick information for the system and the current process in order to provide stats on the cloud page about CPU utilization. Tick counts are monotonically increasing since boot. Find definitions of /proc file info here. http://man7.org/linux/man-pages/man5/proc.5.html

  • Constructor Details

    • LinuxProcFileReader

      public LinuxProcFileReader()
      Constructor.

  • Method Details

    • isWsl

      public boolean isWsl()
      Returns:
      whether this java process is running in Windows Subsystem for Linux environment.

    • getSystemIdleTicks

      public long getSystemIdleTicks()
      Returns:
      ticks the system was idle. in general: idle + busy == 100%

    • getSystemTotalTicks

      public long getSystemTotalTicks()
      Returns:
      ticks the system was up.

    • getProcessTotalTicks

      public long getProcessTotalTicks()
      Returns:
      ticks this process was running.

    • getCpuTicks

      public long[][] getCpuTicks()
      Array of ticks. [cpu number][tick type] tick types are: [0] user ticks [1] system ticks [2] other ticks (i/o) [3] idle ticks
      Returns:
      ticks array for each cpu of the system.

    • getProcessRss

      public long getProcessRss()
      Returns:
      resident set size (RSS) of this process.

    • getProcessCpusAllowed

      public int getProcessCpusAllowed()
      Returns:
      number of CPUs allowed by this process.

    • getProcessNumOpenFds

      public int getProcessNumOpenFds()
      Returns:
      number of currently open fds of this process.

    • getProcessID

      public String getProcessID()
      Returns:
      process id for this node as a String.

    • read

      public void read()
      Read and parse data from /proc/stat and /proc/<pid>/stat. If this doesn't work for some reason, the values will be -1.

    • valid

      public boolean valid()
      Returns:
      true if all the values are ok to use; false otherwise.

    • numSetBitsHex

      public static int numSetBitsHex(String s)
      Returns:
      number of set bits in hexadecimal string (chars must be 0-F)