** open tables
[00] 2021-06-09 01:00:03 mariabackup: Generating a list of tablespaces

** stream ibd - multi threaded (number in brackets is thead id)
[00] 2021-06-09 02:39:13 mariabackup: Starting 16 threads for parallel data files transfer
[14] 2021-06-09 02:39:13 Streaming ./blogs/wp_136126_termmeta.ibd
[05] 2021-06-09 02:39:13 Streaming ./blogs/wp_291951_postmeta.ibd
[13] 2021-06-09 02:39:13 Streaming ./blogs/wp_302193_options.ibd
...

** stream frm (and lock tables) - signle threaded
[00] 2021-06-09 02:54:36 Executing FLUSH TABLES WITH READ LOCK...

[01] 2021-06-09 02:54:40 Streaming ./blogs/wp_301123_term_relationships.frm to <STDOUT>
[01] 2021-06-09 02:54:40 Streaming ./blogs/wp_313552_term_relationships.frm to <STDOUT>
[01] 2021-06-09 02:54:40 Streaming ./blogs/wp_295077_commentmeta.frm to <STDOUT>
[01] 2021-06-09 02:54:40 Streaming ./blogs/wp_304840_links.frm to <STDOUT>

** end
[00] 2021-06-11 04:23:14 Executing FLUSH NO_WRITE_TO_BINLOG ENGINE LOGS..