Hi,

We recently upgraded out MongoDB from community version 3.4.14 to 4.0.1

We see that the compression ratio differs for the same type of data between the version

Hence we did a test and found that compression ratio drastically fell for 3.6+ 

Can you please suggest if any changes has to be made in the configuration of MongoDB or WiredTiger?

Below is the wired tiger configuration we are using

wiredTiger:
collectionConfig:
blockCompressor: zlib
engineConfig:
directoryForIndexes: true
journalCompressor: none
cacheSizeGB: 40
configString: "eviction_dirty_target=60, eviction_dirty_trigger=80, eviction=(threads_min=20,threads_max=20)"

Thanks,

Tanveer