Test #3

Objective

Compare the performance of Duplicati and Duplicacy in the backup of an Evernote repository, which basically consists (90%) of a SQLite database.

Repository: An Evernote data folder, with ~3.47 Gb, of which the database (exb file) represents 3.38 Gb (97%).
Storage: Two local folders, one for Duplicati e another for Duplciacy.
Chunks: both 1 Mb variable default size (Duplicati: ____ kb and Duplicati: 4M).

Perform the full initial backup of the entire folder.
Proceed with normal daily use for a few days, that is, add/edit some notes, representing a few kb of changes per day, and run a daily incremental backup.
At the end, run the internal "optimize" command from Evernote to evaluate the impact.
The repository and storage sizes were measured with Rclone (www.rclone.org)

In the first days, the execution of the two jobs showed that fixed chunks seems to make better use of storage space than the variable chunks:

Uploads were also smaller with fixed chunks

Note 1: The above chart does not show day 1, as there is no "increase" on this day.

Note 2: At day 2, even Evernote not being executed, there was some upload in the backup.

And the upload time was also consistently smaller:

Then, on day 5, the command to "optimize" the Evernote database was executed, which basically consists of a reindexing.

The result was that 2,664 chunks (out of a total of 2,667) were reuploaded:

The use of fixed-size chunks provides better performance for incremental backups of small daily changes with this type of file (Evernote database, that is basically an SQLite file).
Neither setups (fixed and variable chunks) fits well when the database is reindexed. But in this case it is not a limitation of Duplicacy because the entire database must have been modified. Using the optimization command in sync with the Duplicacy prune commands may improve the use of storage space.

REPOSITORY:

1 Mb VAR CHUNK STORAGE:

Storage size by Duplicacy log (kb)	Storage size by Rclone (kb)	Storage increase (kb)	Version	uploaded (All chunks log line) (kb)	backup time
3.313.000	2.945.953		1		00:03:38
3.315.000	2.945.953	0	2	102.846	00:02:16
3.317.000	3.328.283	382.330	3	270.521	00:02:12
3.318.000	3.479.856	151.573	4	148.020	00:02:23
3.317.000	6.417.636	2.937.780	5	2.801.000	00:04:30

1 Mb FIX CHUNK STORAGE:

Storage size by Duplicacy log (kb)	Storage size by Rclone (kb)	Storage increase (kb)	Version	uploaded (All chunks log line) (kb)	backup time
3.313.000	2.946.272		1		00:03:23
3.313.000	2.946.272	0	2	42.151	00:00:11
3.315.000	3.109.595	163.323	3	117.343	00:01:37
3.315.000	3.169.552	59.957	4	58.550	00:01:40
3.314.000	6.107.636	2.938.084	5	2.801.000	00:03:20