[pyarrow] significant increase in memory when connect hdfs and upload files to hdfs

pyarrow version:7.0.0
connect hdfs to get a fileSystem object by pyarrow,the memory increased from 64M to 254M,
then I use this fileSystem object to upload a 2G file to hdfs, the memory increased to 289M
after 10 min, the memory keep the same.
how can i release the memory?

No files, tests, or entry points are named. Start by reproducing the report with pyarrow 7.0.0: connect to HDFS, upload a 2G file, and measure memory before connection, after connection, after upload, and after 10 minutes; done means determining whether the increase is expected and whether the memory can be released.

Written by the indexing model from the issue text.