Uploaded image for project: 'JDK'
  1. JDK
  2. JDK-8213768

Remove the -Xconcurrentio flag and associated code

XMLWordPrintable

    • Icon: CSR CSR
    • Resolution: Approved
    • Icon: P4 P4
    • None
    • hotspot
    • None
    • behavioral
    • minimal
    • Hide
      This was always an "undocumented" flag in that "java -X" does not mention it even back in JDK 1.4. It did end up being informally documented in FAQs and tuning guides, but this was all intended for pre 1.4. e.g.

      https://docs.oracle.com/cd/E19683-01/817-2180-10/pt_chap5.html
      https://www.javaperformancetuning.com/tips/rawtips.shtml

      Some slightly newer pages:

      https://dilipnwebservices.wordpress.com/2013/09/19/little-notes-on-performance-tuning/

      are simply regurgitating text that was over 10 years old at the time and irrelevant.
      Show
      This was always an "undocumented" flag in that "java -X" does not mention it even back in JDK 1.4. It did end up being informally documented in FAQs and tuning guides, but this was all intended for pre 1.4. e.g. https://docs.oracle.com/cd/E19683-01/817-2180-10/pt_chap5.html https://www.javaperformancetuning.com/tips/rawtips.shtml Some slightly newer pages: https://dilipnwebservices.wordpress.com/2013/09/19/little-notes-on-performance-tuning/ are simply regurgitating text that was over 10 years old at the time and irrelevant.
    • add/remove/modify command line option
    • Implementation

      Summary

      Remove the undocumented and very old -Xconcurrentio flag

      Problem

      This flag dates back to the JDK 1.2/1.3 days and was useful primarily on Solaris where it enabled use of LWP synchronization. But that became the default in JDK 1.4. The flag serves no useful purpose and is unlikely to have been used for many years.

      Solution

      Remove the -Xconcurrentio flag

      Specification

      Remove the -Xconcurrentio flag

            dholmes David Holmes
            dholmes David Holmes
            Robbin Ehn
            Votes:
            0 Vote for this issue
            Watchers:
            4 Start watching this issue

              Created:
              Updated:
              Resolved: