On Mon, Apr 23, 2018 at 10:21:01PM -0400, jeffm@xxxxxxxx wrote: > Memory pressure isn't really an issue on this machine, so we > end up using well over 100GB for proc files. Text files at scale! > With these patches applied, running the same testcase, the proc_inode > cache only gets to about 600k objects, which is about 99.7% fewer. I > get that procfs isn't supposed to be scalable, but this is kind of > extreme. :) Easy stuff: * all ->get_link hooks are broken in RCU lookup (use GFP_KERNEL), * "%.*s" for dentry names is probably unnecessary, they're always NUL terminated * kasprintf() does printing twice, since we're kind of care about /proc performance, allocate for the worst case. * "int nlinks = nlink_tgid;" Unsigned police. * (inode->i_mode & S_IFLNK) this is sketchy, S_ISLNK exists.
