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- Path: sparky!uunet!auspex-gw!guy
- From: guy@Auspex.COM (Guy Harris)
- Newsgroups: comp.sys.sun.admin
- Subject: Re: Sun vs. Solbourne console speed
- Message-ID: <15865@auspex-gw.auspex.com>
- Date: 13 Dec 92 20:22:09 GMT
- References: <15848@auspex-gw.auspex.com> <Bz569H.4Cx@rahul.net> <15864@auspex-gw.auspex.com>
- Sender: news@auspex-gw.auspex.com
- Distribution: na
- Organization: Auspex Systems, Santa Clara
- Lines: 41
- Nntp-Posting-Host: auspex.auspex.com
-
- >OK. The *why* is that, as I understand it, they fucked up and forgot to
- >make the interpreter cacheable.
-
- Actually, it was "the primitive text display subroutines". To quote the
- paper "Open Boot Firmware", by Mitch Bradley (Mr. Open Boot), in the
- Winter 1992 USENIX proceedings:
-
- 4.2. Mistakes
-
- The Open Boot architecture is in its second revision (Open
- Boot 2.x). In the second revision, we had the opportunity (or
- luxury!) to correct many of the mistakes we made in version 1.
-
- The problems with version 1 resulted from a number of
- factors, including time pressure, our own ignorance, and "the
- first cut is always wrong" syndrome. Some of those version 1
- problems include:
-
- ...
-
- o Text Display Performance
-
- In some Open Boot implementations, the text display
- performance leaves something to be desired. This is mostly
- attributable to a bug in the code; the primitive text
- display subroutines were supposed to be executed from
- cached RAM, but due to a bug, the cache was not being
- enabled for that page. Consequently, those routines were
- being executed from ROM, which is about 50 times slower
- than cache!
-
- No, I don't know why not enabling the cache caused the routines to be
- executed from ROM, nor do I know whether he meant to say that they were
- being executed from RAM rather than from, if you will, the cache.
-
- In any case, if the intent behind asking "why" this happened was to
- elicit proof of one's theory that it was some Corporate Plot by Sun to
- force people to use window systems, or something such as that, the above
- doesn't provide such proof (of course, *true* conspiracy theorists
- construct their theories in such a way as to be able to explain away
- *all* evidence that contradicts it...).
-