mapleFU commented on issue #38245:
URL: https://github.com/apache/arrow/issues/38245#issuecomment-1759921604

   🤔I think it's expected(though this sounds horrible)
   
   Your file including 5000 columns with dictionary encoding and SNAPPY 
compression. The memory might consitituted by:
   
   1. Reading the footer( the peek memory usage might grows higher when 
deserialize thrift for the footer, maybe you can try to disable statistics, 
this might make reading it a bit faster)
   2. Reading "Physical" Page, which including dictionary page and data page 
for every column, and because they're compressed, for each column, a 
decompressed buffer is used. This make the memory usage larger
   3. when `read_table` is called, the data in parquet would be "materialized" 
to arrow table, which make it worse...
   
   Some advices:
   
   1. Try to disable statistics if you don't want use it. If you really wants 
statistics you can try to disable statistics for some columns. This might not 
helps a lot, but it may reduce some size of this file.
   2. Maybe trying to testing PLAIN encoding or disable compression. I'm not 
advice to just shift to PLAIN or disable compression, but you can have a try. 
It might works well(and might make it worse)


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