From: jnc@mercury.lcs.mit.edu (Noel Chiappa)
To: tuhs@tuhs.org
Subject: [TUHS] 'Huge' file support removed from PWB1
Date: Wed, 8 Mar 2023 08:10:08 -0500 (EST) [thread overview]
Message-ID: <20230308131008.0C2D018C07B@mercury.lcs.mit.edu> (raw)
In PWB1, support for 'huge' files appears to have been removed. If one
compares bmap() in PWB1'S subr.c with V6's, the "'huge' fetch of double
indirect block" code is gone. I guess PWB didn't need very large (> 8*256*512
= 1,048,576 bytes) files? I'm not sure what the _benefits_ of removing it
were, though - unless PWB was generating lots of files of between 7*256*512
and 8*256*512 bytes in length, and they wanted to avoid the overhead of the
double-indirect block? (The savings in code space are derisory - unlike in
LSX/MINI-UNIX.) Anyone know?
Noel
next reply other threads:[~2023-03-08 13:10 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-08 13:10 Noel Chiappa [this message]
2023-03-09 8:21 ` [TUHS] " Kenneth Goodwin
2023-03-09 12:40 ` Jonathan Gray
2023-03-09 15:07 ` Ron Natalie
2023-03-09 15:13 ` Ron Natalie
2023-03-09 17:35 ` arnold
2023-03-09 17:01 ` Tom Ivar Helbekkmo via TUHS
2023-03-09 23:25 ` Clem Cole
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20230308131008.0C2D018C07B@mercury.lcs.mit.edu \
--to=jnc@mercury.lcs.mit.edu \
--cc=tuhs@tuhs.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).