Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83; site hou5e.UUCP Path: utzoo!linus!decvax!harpo!floyd!vax135!ariel!hou5f!hou5e!mat From: mat@hou5e.UUCP (M Terribile) Newsgroups: net.unix-wizards Subject: Re: Shared system routines Message-ID: <680@hou5e.UUCP> Date: Wed, 27-Jul-83 10:19:48 EDT Article-I.D.: hou5e.680 Posted: Wed Jul 27 10:19:48 1983 Date-Received: Wed, 27-Jul-83 21:54:25 EDT References: <505@mit-eddie.UUCP> Organization: American Bell ED&D, Holmdel, NJ Lines: 21 There is one reason for not putting a shared library system on an OS. It is vary hard to do it in a way that is both general and right without sacrificing machine cycles, IO bandwidth, or something else. I have seen it done efficiently, but in a very specific way, to help maintain speed of a UNI*X machine dedicated to a few special applications. I have seen it done generally, on the HP 3000, with HARDWARE SUPPORT. As a result, loading the COBOL compiler can take up over 3 seconds of dedicated disk usage (run-time linking). It IS possible to get around it; the HP's OS has a ``sticky-bit'' type of facility; but the problem affects EVERYTHING that runs on the machine and the difference between a dog of a machine and a smooth--running one lies almost entirely in the technical savvy of the system administrators. Not desireable! Perhaps a middle ground could be found in a multi-kernelized system, with an efficient ``sys call'' facility, but if you are talking about cheap machines (managers DO buy DG machines, you know) it may take a while to happen. Mark Terribile Duke of deNet