Uploaded image for project: 'JDK'
  1. JDK
  2. JDK-8077237

Consider free heap when composing cset for mixed gc

    Details

    • Subcomponent:
      gc
    • CPU:
      generic
    • OS:
      generic

      Description

      for coherence (16g 50% read 50% write) and ycsb hbase workload (100g heap), to avoid to-space exhausted for mixed gc, we have to push G1NewSizePercent down. The default is 5, which can lead to too many young regions, or not enough old regions added to the CSet, so that we run into to-space exhausted.
      On the other hand, pushing G1NewSizePercent to 1 does not give the best performance. For coherence, 2 gives best throughput w/o to-space exhausted. For hbase ycsb, 3 gives best throughput.

      As we discussed, there might be a way to consider free space available when constructing cset mixed gc.This includes lowering G1NewSizePercent enough to avoid to-space exhausted, as well as adding old regions to cset

        Issue Links

          Activity

          Hide
          yuzhang Jenny Zhang added a comment -
          I have some mixed results with coherence( 16g heap)
          id fill heap rate G1NewSizePercent score comments
          312 60 1 20576
          359 60 2 20725
          360 60 3 13870 to-space exhausted, full gcs
          361 50 1 23452
          362 50 2 24322
          363 50 3 25414 full gc happened during warmup
          364 50 4 16688 full gcs

          The gc logs are attached.
          Show
          yuzhang Jenny Zhang added a comment - I have some mixed results with coherence( 16g heap) id fill heap rate G1NewSizePercent score comments 312 60 1 20576 359 60 2 20725 360 60 3 13870 to-space exhausted, full gcs 361 50 1 23452 362 50 2 24322 363 50 3 25414 full gc happened during warmup 364 50 4 16688 full gcs The gc logs are attached.

            People

            • Assignee:
              Unassigned
              Reporter:
              yuzhang Jenny Zhang
            • Votes:
              0 Vote for this issue
              Watchers:
              1 Start watching this issue

              Dates

              • Created:
                Updated: