Id mapper is used by NFS to translate user and group ids into names, and to

translate user and group names into ids. Part of this translation involves

performing an upcall to userspace to request the information.

fs.nfs.idmap_cache_timeout

设置idmapper缓存项的最大寿命,单位是秒

https://www.kernel.org/doc/Documentation/filesystems/nfs/idmapper.txt

https://www.cnblogs.com/tolimit/p/5065761.html