Uploaded image for project: 'JDK'
  1. JDK
  2. JDK-8283474

Include detailed heap object info in CDS map file

    XMLWordPrintable

    Details

    • Subcomponent:
    • Resolved In Build:
      b17

      Description

      Currently the cds.map file produced by "java -Xshare:dump -Xlog:cds+map=trace:file=cds.map:none:filesize=0" prints information of each individual metaspace object.

      This is useful in diagnosing problems with deterministic CDS archive files (such as JDK-8253495)

      For example:

      [ro region 0x00000008004ca000 - 0x0000000800c452e8 7844584 bytes]
      0x00000008004ca000:
      0x00000008004ca000: @@ Symbol 8 [Z
      0x00000008004ca000: 5a5b0002e99effff
      0x00000008004ca008: @@ Symbol 8 [C
      0x00000008004ca008: 435b000299a9ffff
      ...
      0x0000000800bcd838: @@ TypeArrayU1 16
      0x0000000800bcd838: 3e00010000000006 0000000000000000
      0x0000000800bcd848: @@ ConstMethod 104 java.lang.String java.lang.Object.toString()
      0x0000000800bcd848: 0000000000000018 0000000800651da8 0000000000000000 000c00050000000d
      0x0000000800bcd868: 0006001200250024 0006000100010002 ec0000b7590100bb 03b60002b60001b6
      0x0000000800bcd888: b6ec0003b600e600 0003b60005b80004 05c000ffb00006b6 003b002400000000
      0x0000000800bcd8a8: 000100000000003c

      However, there's no such printout for the archived heap objects.

      This RFE adds the following info into the cds.map file.

      [closed heap region 0x00000007bf800000 - 0x00000007bf87e000 516096 bytes]
      0x00000007bf800000: @@ Object [B
      0x00000007bf800000: 00000003f021ab01 0000000000002090
      0x00000007bf800010: @@ Object java.lang.String
      0x00000007bf800010: 0000000d37cfa501 00000000000091d8 f7f0000000010100

        Attachments

          Issue Links

            Activity

              People

              Assignee:
              iklam Ioi Lam
              Reporter:
              iklam Ioi Lam
              Votes:
              0 Vote for this issue
              Watchers:
              3 Start watching this issue

                Dates

                Created:
                Updated:
                Resolved: