Path: ...!weretis.net!feeder9.news.weretis.net!i2pn.org!i2pn2.org!.POSTED!not-for-mail From: mitchalsup@aol.com (MitchAlsup1) Newsgroups: comp.arch Subject: Re: ancient OS history, ARM is sort of channeling the IBM 360 Date: Sun, 30 Jun 2024 01:59:23 +0000 Organization: Rocksolid Light Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Info: i2pn2.org; logging-data="1639571"; mail-complaints-to="usenet@i2pn2.org"; posting-account="65wTazMNTleAJDh/pRqmKE7ADni/0wesT78+pyiDW8A"; User-Agent: Rocksolid Light X-Rslight-Site: $2y$10$RilxofvdX2wVIO1ntoS1WOddPsh2ILcxcGXGJNN60JUvdlahu09Xy X-Rslight-Posting-User: ac58ceb75ea22753186dae54d967fed894c3dce8 X-Spam-Checker-Version: SpamAssassin 4.0.0 Bytes: 1976 Lines: 23 Lawrence D'Oliveiro wrote: > On Sat, 29 Jun 2024 18:22:04 -0000 (UTC), John Levine wrote: > >> ... more often than not locate I/O is faster and easier. > > Given all the caveats and restrictions, “easier” is not how I would > describe it. > > But perhaps we’re talking at cross-purposes. If Mitch did his TSS and > PL/I > stuff in the 1970s, while you’re talking about the 1960s, then that > could > explain it. By the 1970s, CPU/RAM speeds had improved to the point where > copying records a few hundred bytes at a time between buffers was not > the > performance bottleneck; disk I/O was. In particular, my PL/1 programs were not I/O bound. >> When you touched the address, the page fault caused the I/O. > > There seems to be this assumption that the paging mechanism is some kind > of clever way of doing I/O. It’s not.