Path: utzoo!utgpu!watmath!att!tut.cis.ohio-state.edu!ukma!rex!ginosko!husc6!rice!sun-spots-request From: sgf@cfm.brown.edu (William Quayle) Newsgroups: comp.sys.sun Subject: Re: extending the max number of open files. Keywords: SunOS Message-ID: <608@brazos.Rice.edu> Date: 27 Jul 89 20:17:06 GMT Sender: root@rice.edu Organization: Sun-Spots Lines: 16 Approved: Sun-Spots@rice.edu X-Sun-Spots-Digest: Volume 8, Issue 88, message 8 of 16 billq@cbnewsc.att.com (William Quayle) writes: >The max number of open files is compiled into the kernel, and is >determined using the "MAXUSERS" parameter in the configuration file... Well, the system maintains a set of structures describing open files, but it refers to all open files on the system. The size of the set is determined at build time by an arcane formula (in /usr/sys/conf/param.c in SunOS 3.x) based on MAXUSERS from the conf file. If you need to increase it muck around with the specific formula for it in param.c. Just arbitrarily bumping up MAXUSERS can get you into other messes. The problem that most people run into and complain about is the limit on open files per process. In 3.3 it's 30 and in 4.x it's 64 and is called "NOFILE" (found in /usr/include/sys/param.h). There are several grungy things in the kernel that make changing this unpretty (eg, the way the descripter is encoded in ioctl parameters passed to the kernel).