rangareddy commented on issue #5351:
URL: https://github.com/apache/hudi/issues/5351#issuecomment-5101250244

   This issue was reviewed as part of the JIRA-migrated backlog triage.
   
   Findings: This is a performance question rather than an identified defect, 
and the measurement that settles it is already on the thread. Writing the same 
1.37M-row / 308-column dataset as plain Spark parquet took **568s** against 
Hudi's **605s** -- roughly a 6% difference, which leaves no Hudi-specific 
overhead to explain. Building from master brought it to 492s.
   
   The expectation gap comes from the other comparison in the thread: a 
single-node pandas gzip parquet write at ~2m4s. That is not comparable to a 
distributed Spark write of the same data -- the Spark job pays for 
partitioning, shuffle, task scheduling and (for Hudi) key generation and index 
lookup, on a single `t2.xlarge` in this case. The right baseline for "is Hudi 
slow here" is `df.write.format("parquet")` on the same cluster, and by that 
baseline it is not.
   
   For the shape of workload described here -- a large initial/immutable load 
into a new table -- `bulk_insert` rather than `insert`/`upsert` is the config 
that matters, since it skips index lookup and small-file handling entirely; see 
the [performance docs](https://hudi.apache.org/docs/performance#bulk-insert). 
That suggestion was made on 2022-11-04 and never followed up, and there has 
been no substantive discussion since.
   
   Closing as stale, since there is no isolated Hudi defect here for a 
performance validation pass to reproduce, and the report is against 0.8.0 -- a 
version whose write path has been substantially rewritten since. If write 
throughput is still a problem for you on a recent version (1.0.x / 1.1.x / 
1.2.0), please open a fresh issue with the Hudi version, the write operation 
and configs, the cluster shape, and the Spark UI stage timings, and we can look 
at where the time is actually going.


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