Bugzilla

I created a profile with 160k bookmarks and 100k tags, but searching in the library is still quite fast for me, my specs are more or less aligned with the ones in comment 0 (5700x3D, 32GB ram, ssd Samsung). There must be some additional condition, for which I may need additional statistics for your database. Attaching a txt log from about:support may help as it contains counts of entries per each table.

For now the only thing I can suggest, after a BACKUP OF THE WHOLE PROFILE FOLDER, is to copy your places.sqlite into a new separate profile and try to launch that new profile with Firefox Nightly... if the problem is solved in Nightly, then it's because of the query planner changes in SQLite 3.47 that were addressed in 3.49. 
Otherwise, I will have to find a way to replicate this database contents with dummy data.

I created a profile with 160k bookmarks and 100k tags, but searching in the library is still quite fast for me, my specs are more or less aligned with the ones in comment 0 (5800x3D, 32GB ram, ssd Samsung). There must be some additional condition, for which I may need additional statistics for your database. Attaching a txt log from about:support may help as it contains counts of entries per each table.

For now the only thing I can suggest, after a BACKUP OF THE WHOLE PROFILE FOLDER, is to copy your places.sqlite into a new separate profile and try to launch that new profile with Firefox Nightly... if the problem is solved in Nightly, then it's because of the query planner changes in SQLite 3.47 that were addressed in 3.49. 
Otherwise, I will have to find a way to replicate this database contents with dummy data.

I created a profile with 160k bookmarks and 100k tags, but searching in the library is still quite fast for me, my specs are more or less aligned with the ones in comment 0 (5800x3D, 32GB ram, ssd Samsung). There must be some additional condition, for which I may need additional statistics for your database. Attaching a txt log from about:support may help as it contains counts of entries per each table.

For now the only thing I can suggest, after a BACKUP OF THE WHOLE PROFILE FOLDER, is to copy your places.sqlite into a new separate profile and try to launch that new profile with Firefox Nightly... if the problem is solved in Nightly, then it's because of the query planner changes in SQLite 3.47 that were addressed in 3.49.  Then it's just matter of awaiting for the update.
Otherwise, I will have to find a way to replicate this database contents with dummy data.