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+ [TABLE]
[TR]
[TD]Version[/TD]
[TD]Raw size[/TD]
[TD]Storage size[/TD]
[TD]Comp Ratio[/TD]
[/TR]
[TR]
[TD]4.0[/TD]
[TD]10378066324[/TD]
[TD]1594658816[/TD]
[TD]6.5x[/TD]
[/TR]
[TR]
[TD]3.6[/TD]
[TD]10378066324[/TD]
[TD]1599205376[/TD]
[TD]6.49x[/TD]
[/TR]
[TR]
[TD]3.4[/TD]
[TD]10378066324[/TD]
[TD]634499072[/TD]
[TD]16.35x[/TD]
[/TR]
[/TABLE]
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