ISSUE SUMMARY
MongoDB may cause excessive disk space usage when Zlib compression is enabled.

USER IMPACT
Disk space could be consumed rapidly causing out of space errors. Upgrading to a version that contains the fix will not reclaim the excess disk space; for that, a re-write of the collection data with a version containing the fix is needed (e.g.: initial sync).

WORKAROUNDS
There is currently no workaround for this issue.

AFFECTED VERSIONS
MongoDB production releases 3.6.0 through 3.6.8 as well as 4.0.0 and 4.0.1 are affected by this issue.

FIX VERSION
This issue is fixed in MongoDB version 3.6.9 and 4.0.2 by WT-3968.

RESOLUTION DETAILS
Please consider upgrading to 3.6.9 or 4.0.2 if this issue impacts you.