@Loic , voilà ce que top me remonte:
top - 15:51:02 up 2:41, 1 user, load average: 0.59, 0.77, 0.86
Tasks: 127 total, 10 running, 116 sleeping, 0 stopped, 1 zombie
%Cpu(s): 39.1 us, 14.0 sy, 0.0 ni, 46.2 id, 0.0 wa, 0.0 hi, 0.7 si, 0.0 st
MiB Mem : 3947.8 total, 665.9 free, 719.7 used, 2562.2 buff/cache
MiB Swap: 1024.0 total, 1024.0 free, 0.0 used. 2960.7 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
13635 www-data 20 0 175500 51552 30196 R 16.7 1.3 0:00.50 ffmpeg
13639 www-data 20 0 219676 35632 26076 S 10.3 0.9 0:00.31 php
13690 www-data 20 0 219688 37384 27832 R 9.7 0.9 0:00.29 php
13703 www-data 20 0 219688 36324 26772 R 7.3 0.9 0:00.22 php
13715 www-data 20 0 217628 32800 25304 R 5.0 0.8 0:00.15 php
13375 www-data 20 0 231372 35268 18000 S 2.7 0.9 0:00.46 apache2
13727 www-data 20 0 217432 30840 23512 R 2.0 0.8 0:00.06 php
13379 www-data 20 0 231360 33416 16152 S 1.3 0.8 0:00.73 apache2
558 root 20 0 691456 22984 8916 S 1.0 0.6 0:54.12 fail2ban-server
693 mysql 20 0 1608060 182484 17208 S 1.0 4.5 1:54.46 mysqld
13390 www-data 20 0 225444 28844 17420 S 1.0 0.7 0:00.24 apache2
7335 root 20 0 4876036 86560 37548 S 0.7 2.1 0:28.66 node
10 root 20 0 0 0 0 I 0.3 0.0 0:10.61 rcu_sched
17 root 20 0 0 0 0 R 0.3 0.0 0:00.70 ksoftirqd/1
587 ntp 20 0 73612 3080 2568 S 0.3 0.1 0:00.81 ntpd
1901 www-data 20 0 630776 33432 8240 S 0.3 0.8 0:18.89 python3
12448 root 20 0 0 0 0 I 0.3 0.0 0:00.01 kworker/1:1-events
13395 www-data 20 0 231340 32924 15728 S 0.3 0.8 0:00.39 apache2
13397 www-data 20 0 224376 27812 17468 S 0.3 0.7 0:00.09 apache2
1 root 20 0 99788 9504 7064 S 0.0 0.2 0:03.69 systemd
2 root 20 0 0 0 0 S 0.0 0.0 0:00.01 kthreadd
3 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 rcu_gp
4 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 rcu_par_gp
6 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kworker/0:0H
8 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 mm_percpu_wq
9 root 20 0 0 0 0 S 0.0 0.0 0:03.17 ksoftirqd/0
11 root 20 0 0 0 0 I 0.0 0.0 0:00.00 rcu_bh
12 root rt 0 0 0 0 S 0.0 0.0 0:00.11 migration/0
14 root 20 0 0 0 0 S 0.0 0.0 0:00.04 cpuhp/0
15 root 20 0 0 0 0 S 0.0 0.0 0:00.00 cpuhp/1
16 root rt 0 0 0 0 S 0.0 0.0 0:00.10 migration/1
19 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kworker/1:0H-kblockd
20 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kdevtmpfs
21 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 netns
22 root 20 0 0 0 0 S 0.0 0.0 0:00.02 kauditd
24 root 20 0 0 0 0 S 0.0 0.0 0:00.00 khungtaskd
25 root 20 0 0 0 0 S 0.0 0.0 0:00.00 oom_reaper
26 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 writeback
27 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kcompactd0
28 root 25 5 0 0 0 S 0.0 0.0 0:00.00 ksmd
29 root 39 19 0 0 0 S 0.0 0.0 0:01.61 khugepaged
30 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 crypto
31 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kintegrityd
32 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kblockd
33 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 edac-poller
34 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 devfreq_wq
35 root rt 0 0 0 0 S 0.0 0.0 0:00.00 watchdogd
38 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kswapd0
56 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kthrotld
57 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 acpi_thermal_pm
59 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 ipv6_addrconf
68 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kstrp
71 root -51 0 0 0 0 S 0.0 0.0 0:00.00 irq/43-ACPI:Eve
113 root 0 -20 0 0 0 I 0.0 0.0 0:02.30 kworker/0:1H-kblockd
114 root 20 0 0 0 0 S 0.0 0.0 0:00.00 scsi_eh_0
115 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 scsi_tmf_0
139 root 0 -20 0 0 0 I 0.0 0.0 0:00.88 kworker/1:1H-kblockd
143 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kworker/u5:0
145 root 20 0 0 0 0 S 0.0 0.0 0:03.93 jbd2/vda2-8
146 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 ext4-rsv-conver
157 root 20 0 0 0 0 S 0.0 0.0 0:00.02 hwrng
Le démon MySQL ne semble pas super chargé… 
Je tente la même procédure de restauration depuis une toute nouvelle VM… pour comparer et déjà le message la console va plus loin alors qu’il en est à la même étape de restauration de la DB dans les logs…
Et là le processus Mysqld bosse à fond!
top - 16:09:15 up 13 min, 1 user, load average: 8.00, 4.70, 2.33
Tasks: 143 total, 18 running, 125 sleeping, 0 stopped, 0 zombie
%Cpu(s): 83.0 us, 17.0 sy, 0.0 ni, 0.0 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
MiB Mem : 2749.2 total, 74.0 free, 556.3 used, 2118.8 buff/cache
MiB Swap: 1024.0 total, 1023.5 free, 0.5 used. 1970.0 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
771 mysql 20 0 1145548 224844 16924 S 10.3 8.0 1:07.69 mysqld
8105 root 20 0 30520 25072 7500 R 5.3 0.9 0:01.60 pip3
8281 www-data 20 0 219296 40980 31376 R 5.0 1.5 0:00.59 php
8313 www-data 20 0 219268 39100 29556 R 5.0 1.4 0:00.46 php
8369 www-data 20 0 219416 36340 26812 R 5.0 1.3 0:00.27 php
8402 www-data 20 0 219340 35504 25984 R 5.0 1.3 0:00.20 php
8421 www-data 20 0 217192 33080 25620 R 5.0 1.2 0:00.16 php
8243 www-data 20 0 219240 42132 32524 R 4.7 1.5 0:00.66 php
8335 www-data 20 0 219228 37400 27880 R 4.7 1.3 0:00.34 php
8377 www-data 20 0 219300 36140 26620 R 4.7 1.3 0:00.26 php
8381 www-data 20 0 219300 36220 26700 R 4.7 1.3 0:00.26 php
8383 www-data 20 0 219228 35988 26464 S 4.7 1.3 0:00.24 php
8359 www-data 20 0 219228 36688 27176 S 4.4 1.3 0:00.28 php
8441 www-data 20 0 217036 31300 23884 R 3.8 1.1 0:00.12 php
8342 www-data 20 0 219228 36916 27396 S 3.1 1.3 0:00.29 php
766 www-data 20 0 221372 25660 16840 R 2.8 0.9 0:01.53 apache2
8466 www-data 20 0 217000 30864 23460 R 1.9 1.1 0:00.06 php
Et sur cette VM vierge, la restauration avance bien plus vite:
Disable all scenario OK
Unpacking backup...
OK
Deleting database...Disabling constraints...OK
Deleting table : cmd ...
OK
Deleting table : config ...OK
Deleting table : cron ...OK
Deleting table : dataStore ...OK
Deleting table : eqLogic ...OK
Deleting table : eqReal ...OK
Deleting table : history ...OK
Deleting table : historyArch ...OK
Deleting table : interactDef ...OK
Deleting table : interactQuery ...OK
Deleting table : listener ...OK
Deleting table : message ...OK
Deleting table : note ...OK
Deleting table : object ...OK
Deleting table : plan ...OK
Deleting table : plan3d ...OK
Deleting table : plan3dHeader ...OK
Deleting table : planHeader ...OK
Deleting table : scenario ...OK
Deleting table : scenarioElement ...OK
Deleting table : scenarioExpression ...OK
Deleting table : scenarioSubElement ...OK
Deleting table : timeline ...OK
Deleting table : update ...OK
Deleting table : user ...OK
Deleting table : view ...OK
Deleting table : viewData ...OK
Deleting table : viewZone ...OK
Deleting table : widgets ...OK
Restoring database from backup...OK
Enable back constraints...OK
Restoring cache...OK
sudo: yarn: command not found
dpkg-query: package 'netcat' is not installed and no information is available
Use dpkg --info (= dpkg-deb --info) to examine archive files.
Check jeedom consistency...[START CONSISTENCY]
[START CHECK AND FIX DB]
Fix : ALTER TABLE `cmd` DROP INDEX `logicalID`;
Fix :
CREATE INDEX `logicalID` ON `cmd` (`logicalId` ASC)
Fix : CREATE INDEX `logicalID` ON `cmd` (`logicalId` ASC)***ERROR*** [MySQL] Error code : 42000 (1071). Specified key was too long; max key length is 3072 byte
s : CREATE INDEX `logicalID` ON `cmd` (`logicalId` ASC)
[END CHECK AND FIX DB]
Check jeedom package...***ERROR*** Installation de package impossible car il y a déjà une installation en cours
Check jeedom database...
Fix : CREATE INDEX `logicalID` ON `cmd` (`logicalId` ASC)
Fix : CREATE INDEX `logicalID` ON `cmd` (`logicalId` ASC)***ERROR*** [MySQL] Error code : 42000 (1071). Specified key was too long; max key length is 3072 byte
s : CREATE INDEX `logicalID` ON `cmd` (`logicalId` ASC)
Check crons...
Check filesystem right...