Hi, we recently upgraded our cluster (Phoenix 4.3 – HDP 2.2) and I’m seeing a significant degradation in performance. I am going through the MR counters for a Phoenix CsvBulkLoad job and I am hoping you can help me understand some things.
There is a base table with 4 index tables, so a total of 5 MR jobs run – one for each table. Here are the counters for an index table MR job: Note two things – the Input and output are the same number as expected There seems to be a lot spilled records. =========================================================== Combine input records 0 0 0 Combine output records 0 0 0 CPU time spent (ms) 1800380 156630 1957010 Failed Shuffles 0 0 0 GC time elapsed (ms) 39738 1923 41661 Input split bytes 690 0 690 Map input records 13637198 0 13637198 Map output bytes 2144112474 0 2144112474 Map output materialized bytes 2171387170 0 2171387170 Map output records 13637198 0 13637198 Merged Map outputs 0 50 50 Physical memory (bytes) snapshot 8493744128 10708692992 19202437120 Reduce input groups 0 13637198 13637198 Reduce input records 0 13637198 13637198 Reduce output records 0 13637198 13637198 Reduce shuffle bytes 0 2171387170 2171387170 Shuffled Maps 0 50 50 Spilled Records 13637198 13637198 27274396 Total committed heap usage (bytes) 11780751360 26862419968 38643171328 Virtual memory (bytes) snapshot 25903271936 96590065664 122493337600 =========================================================== Here are the counters for the main table MR job Please note the input records are correct – same as above The output records are many times the input The output bytes are many times the output from above The amount of spilled records is many times the number of input records and twice the number of output records =========================================================== Combine input records 0 0 0 Combine output records 0 0 0 CPU time spent (ms) 5059340 2035910 7095250 Failed Shuffles 0 0 0 GC time elapsed (ms) 38937 13748 52685 Input split bytes 690 0 690 Map input records 13637198 0 13637198 Map output bytes 59638106406 0 59638106406 Map output materialized bytes 60702718624 0 60702718624 Map output records 531850722 0 531850722 Merged Map outputs 0 50 50 Physical memory (bytes) snapshot 8398745600 2756530176 11155275776 Reduce input groups 0 13637198 13637198 Reduce input records 0 531850722 531850722 Reduce output records 0 531850722 531850722 Reduce shuffle bytes 0 60702718624 60702718624 Shuffled Maps 0 50 50 Spilled Records 1063701444 531850722 1595552166 Total committed heap usage (bytes) 10136059904 19488309248 29624369152 Virtual memory (bytes) snapshot 25926946816 96562970624 122489917440 =========================================================== Can you help me understand why this is how I can tune this? Thanks, Ralph __________________________________________________ Ralph Perko Pacific Northwest National Laboratory (509) 375-2272 [email protected]
