As a result of IMPALA-4983, the 1.7.5 version of LZ4 in the toolchain has
been rebuilt as of toolchain build 349-1b15a6c8f4 to include optimization
flags.
On another thread we're talking about ways to get
bin/bootstrap_toolchain.py to notice this change automatically. For the
time being, if you want to be sure you have the latest LZ4 version
(important for performance), do something like the following:
rm -rf ${IMPALA_TOOLCHAIN}/lz4-1.7.5/
cd ${IMPALA_HOME} && . bin/impala-config.sh
bin/bootstrap_toolchain.py
