Author: trasz Date: Sat Nov 10 23:07:46 2018 New Revision: 340339 URL: https://svnweb.freebsd.org/changeset/base/340339
Log: Don't call stat(2) on nsswitch.conf(5) every time nsdispatch(3) and dependent functions (eg getpwname(3)) get called. This can improve performance of binaries that perform a lot of name lookups, such as gssd(8). It also matches documented behaviour of Linux and Solaris. The old code is left in place, should anyone need it, guarded by #ifdef NS_REREAD_CONF. Reviewed by: imp, bcr MFC after: 2 weeks Relnotes: yes Sponsored by: DARPA, AFRL Differential Revision: https://reviews.freebsd.org/D17934 Modified: head/lib/libc/net/nsdispatch.c head/share/man/man5/nsswitch.conf.5 Modified: head/lib/libc/net/nsdispatch.c ============================================================================== --- head/lib/libc/net/nsdispatch.c Sat Nov 10 22:14:09 2018 (r340338) +++ head/lib/libc/net/nsdispatch.c Sat Nov 10 23:07:46 2018 (r340339) @@ -335,6 +335,7 @@ static int nss_configure(void) { static time_t confmod; + static int already_initialized = 0; struct stat statbuf; int result, isthreaded; const char *path; @@ -352,6 +353,16 @@ nss_configure(void) if (path == NULL) #endif path = _PATH_NS_CONF; +#ifndef NS_REREAD_CONF + /* + * Define NS_REREAD_CONF to have nsswitch notice changes + * to nsswitch.conf(5) during runtime. This involves calling + * stat(2) every time, which can result in performance hit. + */ + if (already_initialized) + return (0); + already_initialized = 1; +#endif /* NS_REREAD_CONF */ if (stat(path, &statbuf) != 0) return (0); if (statbuf.st_mtime <= confmod) Modified: head/share/man/man5/nsswitch.conf.5 ============================================================================== --- head/share/man/man5/nsswitch.conf.5 Sat Nov 10 22:14:09 2018 (r340338) +++ head/share/man/man5/nsswitch.conf.5 Sat Nov 10 23:07:46 2018 (r340339) @@ -33,7 +33,7 @@ .\" .\" $FreeBSD$ .\" -.Dd June 6, 2016 +.Dd November 10, 2018 .Dt NSSWITCH.CONF 5 .Os .Sh NAME @@ -340,6 +340,12 @@ sets a policy of "if the user is notfound in nis, do n This treats nis as the authoritative source of information, except when the server is down. .Sh NOTES +The +.Nm +file is parsed by each program only once. +Subsequent changes will not be applied until the program +is restarted. +.Pp If system got compiled with .Va WITHOUT_NIS you have to remove _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "[email protected]"
