rhel7: The number of nfsd threads is not increased from 8 to the number given by "threads" in "[nfsd]" section in the file "/etc/nfs.conf"

Issue

• The number of nfsd threads is not increased from 8 to the number given by "threads" in "[nfsd]" section in the file /etc/nfs.conf
• 1. Set "threads=20" in "[nfsd]" section in the file "/etc/nfs.conf"

# cat /etc/nfs.conf | awk '/\[nfsd\]/,/threads/'
[nfsd]
 debug=0
 threads=20

• 2. If "RPCNFSDCOUNT" is specified in the file /etc/sysconfig/nfs, it will be applied for backward compatibility in RHEL7. So make sure that there is NO "RPCNFSDCOUNT" value specified in the file "/etc/sysconfig/nfs.

# grep RPCNFSD /etc/sysconfig/nfs
#RPCNFSDARGS=""
#RPCNFSDCOUNT=16

• 3. Start nfs-server.service and we will find the number of nfsd threads is not increased from 8 to 20 though "threads=20" is specified in the file "/etc/nfs.conf"

# systemctl is-enabled nfs-server.service
enabled

# systemctl status nfs-server.service
● nfs-server.service - NFS server and services
   Loaded: loaded (/usr/lib/systemd/system/nfs-server.service; enabled; vendor preset: disabled)
  Drop-In: /run/systemd/generator/nfs-server.service.d
           └─order-with-mounts.conf
   Active: inactive (dead) since Fri 2019-08-02 13:33:02 JST; 2s ago
  Process: 5559 ExecStopPost=/usr/sbin/exportfs -f (code=exited, status=0/SUCCESS)
  Process: 5556 ExecStopPost=/usr/sbin/exportfs -au (code=exited, status=0/SUCCESS)
  Process: 5555 ExecStop=/usr/sbin/rpc.nfsd 0 (code=exited, status=0/SUCCESS)
  Process: 5419 ExecStartPost=/bin/sh -c if systemctl -q is-active gssproxy; then systemctl restart gssproxy ; fi (code=exited, status=0/SUCCESS)
  Process: 5402 ExecStart=/usr/sbin/rpc.nfsd $RPCNFSDARGS (code=exited, status=0/SUCCESS)
  Process: 5400 ExecStartPre=/usr/sbin/exportfs -r (code=exited, status=0/SUCCESS)
 Main PID: 5402 (code=exited, status=0/SUCCESS)

# systemctl start nfs-server.service
# systemctl status nfs-server.service
● nfs-server.service - NFS server and services
   Loaded: loaded (/usr/lib/systemd/system/nfs-server.service; enabled; vendor preset: disabled)
  Drop-In: /run/systemd/generator/nfs-server.service.d
           └─order-with-mounts.conf
   Active: active (exited) since Fri 2019-08-02 13:33:24 JST; 2s ago
  Process: 5559 ExecStopPost=/usr/sbin/exportfs -f (code=exited, status=0/SUCCESS)
  Process: 5556 ExecStopPost=/usr/sbin/exportfs -au (code=exited, status=0/SUCCESS)
  Process: 5555 ExecStop=/usr/sbin/rpc.nfsd 0 (code=exited, status=0/SUCCESS)
  Process: 5615 ExecStartPost=/bin/sh -c if systemctl -q is-active gssproxy; then systemctl restart gssproxy ; fi (code=exited, status=0/SUCCESS)
  Process: 5597 ExecStart=/usr/sbin/rpc.nfsd $RPCNFSDARGS (code=exited, status=0/SUCCESS)
  Process: 5596 ExecStartPre=/usr/sbin/exportfs -r (code=exited, status=0/SUCCESS)
 Main PID: 5597 (code=exited, status=0/SUCCESS)
   CGroup: /system.slice/nfs-server.service

# cat /proc/net/rpc/nfsd | grep th
th 8 0 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000

# ps aux | grep nfsd
root      4555  0.0  0.0      0     0 ?        S<   13:24   0:00 [nfsd4_callbacks]
root      4561  0.0  0.0      0     0 ?        S    13:24   0:00 [nfsd]
root      4562  0.0  0.0      0     0 ?        S    13:24   0:00 [nfsd]
root      4563  0.0  0.0      0     0 ?        S    13:24   0:00 [nfsd]
root      4564  0.0  0.0      0     0 ?        S    13:24   0:00 [nfsd]
root      4565  0.0  0.0      0     0 ?        S    13:24   0:00 [nfsd]
root      4566  0.0  0.0      0     0 ?        S    13:24   0:00 [nfsd]
root      4567  0.0  0.0      0     0 ?        S    13:24   0:00 [nfsd]
root      4568  0.0  0.0      0     0 ?        S    13:24   0:00 [nfsd]
root      4660  0.0  0.0 112704   976 pts/0    S+   13:25   0:00 grep --color=auto nfsd