and iostats:


04/10/21 10:51:14
avg-cpu:  %user   %nice %system %iowait  %steal   %idle
          2.09    0.00    1.56    0.02    0.00   96.33

Device            r/s     rkB/s   rrqm/s  %rrqm r_await rareq-sz     w/s     wkB/s   wrqm/s  %wrqm w_await wareq-sz     d/s     dkB/s   drqm/s  %drqm d_await dareq-sz     f/s f_await  aqu-sz  %util
nvme0n1          0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00    0.00    0.00   0.00
nvme1n1          0.00      0.00     0.00   0.00    0.00     0.00    7.10     39.20     1.40  16.47    1.68     5.52    0.00      0.00     0.00   0.00    0.00     0.00    0.10    1.00    0.01   0.19
sda              0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00    0.00    0.00   0.00
zram0            0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00    0.00    0.00   0.00


04/10/21 10:51:40
avg-cpu:  %user   %nice %system %iowait  %steal   %idle
          2.31    0.00    1.60   10.86    0.00   85.24

Device            r/s     rkB/s   rrqm/s  %rrqm r_await rareq-sz     w/s     wkB/s   wrqm/s  %wrqm w_await wareq-sz     d/s     dkB/s   drqm/s  %drqm d_await dareq-sz     f/s f_await  aqu-sz  %util
nvme0n1          0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00    0.00    0.00   0.00
nvme1n1          0.00      0.00     0.00   0.00    0.00     0.00    0.71      3.43     0.15  17.39   12.16     4.84    0.00      0.00     0.00   0.00    0.00     0.00    0.04    1.00    0.01   0.19
sda              0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00    0.00    0.00   0.00
zram0            0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00    0.00    0.00   0.00


04/10/21 10:51:50
avg-cpu:  %user   %nice %system %iowait  %steal   %idle
          2.59    0.00    1.69    0.17    0.00   95.55

Device            r/s     rkB/s   rrqm/s  %rrqm r_await rareq-sz     w/s     wkB/s   wrqm/s  %wrqm w_await wareq-sz     d/s     dkB/s   drqm/s  %drqm d_await dareq-sz     f/s f_await  aqu-sz  %util
nvme0n1          0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00    0.00    0.00   0.00
nvme1n1          0.00      0.00     0.00   0.00    0.00     0.00    1.40     11.20     1.40  50.00   12.36     8.00    0.00      0.00     0.00   0.00    0.00     0.00    0.20    1.00    0.02   0.50
sda              0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00    0.00    0.00   0.00
zram0            0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00      0.00     0.00   0.00    0.00     0.00    0.00    0.00    0.00   0.00

So nothing obvious on the disks of the server. I am pretty sure this is an NFS issue ...