Synchronization of existing content on both sides with a fresh database takes longer than it used to

A customer reported to us that launching Drive after having removed .nuxeo-drive with a large number of existing files on both sides takes longer than it used to, see https://jira.nuxeo.com/browse/SUPNXP-11570?focusedCommentId=194141&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-194141.

Seems that problem appeared since https://github.com/nuxeo/nuxeo-drive/commit/bbf342e : NXDRIVE-107: Add inconsistent clean, fix LastKnownState constructor

Tested with > 500 docs server-side using the latest revision e9ba29f, takes 1 min 22 s, then the one just before bbf342e: da3b4ad, takes only 16 s.
See attached logs for each case.

In nxdrive.e9ba29f.log we can see for each doc "Automated conflict resolution using digest for..." which might make the difference.