[jira] [Created] (KUDU-3418) Punch hole feature not supported on disks with FDE enabled

["Ashwani Raina (Jira)" <ji...@apache.org>]

Ashwani Raina created KUDU-3418:
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             Summary: Punch hole feature not supported on disks with FDE enabled
                 Key: KUDU-3418
                 URL: https://issues.apache.org/jira/browse/KUDU-3418
             Project: Kudu
          Issue Type: Bug
          Components: master, tserver
    Affects Versions: 1.13.0, 1.14.0, 1.15.0, 1.16.0
            Reporter: Ashwani Raina
            Assignee: Ashwani Raina


In some scenarios, rowsets can accumulate a lot of data, so {{kudu-master}} and {{kudu-tserver}} processes grow far beyond the hard memory limit (controlled by the {{\-\-memory_limit_hard_bytes}} flag) when running CompactRowSetsOp.  In some cases, a Kudu server process consumes all the available memory, so that the OS might invoke the OOM killer.

At this point I'm not yet sure about the exact versions affected, and what leads to accumulating so much data in flushed rowsets, but I know that 1.13, 1.14, 1.15 and 1.16 are  affected.  It's also not clear whether the actual regression is in allowing the flushed rowsets growing that big.

There is a reproduction scenario for this bug with {{kudu-master}} using the real data from the fields.  With that data, {{kudu fs list}} reveals a rowset with many UNDOs: see the attached {{fs_list.before}} file.  When starting {{kudu-master}} with the data, the process memory usage eventually peaked with about 25GByte of RSS while running CompactRowSetsOp, and then the RSS eventually subsides down to about 200MByte once the CompactRowSetsOp is completed.

I also attached several SVG files generated by the TCMalloc's pprof from the memory profile snapshots output by {{kudu-master}} when configured to dump allocation stats every 512 MBytes.  I generated the SVG reports for profiles attributed to the highest memory usage:
{noformat}
Dumping heap profile to /opt/tmp/master/nn1/profile.0270.heap (24573 MB currently in use)
Dumping heap profile to /opt/tmp/master/nn1/profile.0283.heap (64594 MB allocated cumulatively, 13221 MB currently in use)
Dumping heap profile to /opt/tmp/master/nn1/profile.0296.heap (77908 MB allocated cumulatively, 12110 MB currently in use)
Dumping heap profile to /opt/tmp/master/nn1/profile.0308.heap (90197 MB allocated cumulatively, 12406 MB currently in use)
Dumping heap profile to /opt/tmp/master/nn1/profile.0332.heap (114775 MB allocated cumulatively, 23884 MB currently in use)
Dumping heap profile to /opt/tmp/master/nn1/profile.0344.heap (127064 MB allocated cumulatively, 12648 MB currently in use)
{noformat}

The report from the compaction doesn't look like anything extraordinary (except for the duration):
{noformat}
I20221012 10:45:49.684247 101750 maintenance_manager.cc:603] P 68dbea0ec022440d9fc282099a8656cb: CompactRowSetsOp(00000000000000000000000000000000) complete. Timing: real 522.617s     user 471.783s   sys 46.588s Metrics: {"bytes_written":1665145,"cfile_cache_hit":846,"cfile_cache_hit_bytes":14723646,"cfile_cache_miss":1786556,"cfile_cache_miss_bytes":4065589152,"cfile_init":7,"delta_iterators_relevant":1558,"dirs.queue_time_us":220086,"dirs.run_cpu_time_us":89219,"dirs.run_wall_time_us":89163,"drs_written":1,"fdatasync":15,"fdatasync_us":150709,"lbm_read_time_us":11120726,"lbm_reads_1-10_ms":1,"lbm_reads_lt_1ms":1786583,"lbm_write_time_us":14120016,"lbm_writes_1-10_ms":3,"lbm_writes_lt_1ms":894069,"mutex_wait_us":108,"num_input_rowsets":5,"rows_written":4043,"spinlock_wait_cycles":14720,"thread_start_us":741,"threads_started":9,"wal-append.queue_time_us":307}
{noformat}



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