* [TUHS] "Webster's Second on the Head of a Pin"? @ 2024-12-29 2:53 Royce Williams 2024-12-29 13:44 ` [TUHS] " Douglas McIlroy ` (2 more replies) 0 siblings, 3 replies; 18+ messages in thread From: Royce Williams @ 2024-12-29 2:53 UTC (permalink / raw) To: TUHS [-- Attachment #1: Type: text/plain, Size: 406 bytes --] Someone I know is seeking the original version of an internal Bell Labs memo from 1974 titled "Webster's Second on the Head of a Pin" by Morris and Thompson. The topic appears to be related to improving the speed of lookups or search. It's cited in a few papers as "Unpublished Technical Memo, Bell Laboratories, Murray Hill, NJ 1974." All I can find online is citations. Any leads appreciated! -- Royce [-- Attachment #2: Type: text/html, Size: 624 bytes --] ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2024-12-29 2:53 [TUHS] "Webster's Second on the Head of a Pin"? Royce Williams @ 2024-12-29 13:44 ` Douglas McIlroy 2024-12-30 21:13 ` sjenkin 2024-12-31 16:37 ` Chet Ramey via TUHS 2024-12-29 16:05 ` Douglas McIlroy 2024-12-30 0:37 ` Warren Toomey via TUHS 2 siblings, 2 replies; 18+ messages in thread From: Douglas McIlroy @ 2024-12-29 13:44 UTC (permalink / raw) To: Royce Williams; +Cc: TUHS I can supply a copy if no one else has beaten me to it. Ron Hardin subsequently pushed the limit even further. Unfortunately, I do not have a record of that work. Doug On Sat, Dec 28, 2024 at 9:54 PM Royce Williams <royce@techsolvency.com> wrote: > > Someone I know is seeking the original version of an internal Bell Labs memo from 1974 titled "Webster's Second on the Head of a Pin" by Morris and Thompson. The topic appears to be related to improving the speed of lookups or search. It's cited in a few papers as "Unpublished Technical Memo, Bell Laboratories, Murray Hill, NJ 1974." All I can find online is citations. Any leads appreciated! > > -- > Royce ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2024-12-29 13:44 ` [TUHS] " Douglas McIlroy @ 2024-12-30 21:13 ` sjenkin 2024-12-31 16:37 ` Chet Ramey via TUHS 1 sibling, 0 replies; 18+ messages in thread From: sjenkin @ 2024-12-30 21:13 UTC (permalink / raw) To: TUHS; +Cc: Computer Old Farts Followers Not dissimilar work at AT&T Research ~2000 - compressing fixed-length records, better than gzip, +30% for similar compute time. ‘pzip’ - Adam Bushman & Glen Fowler <https://web.archive.org/web/20041019142227/http://www.research.att.com/~gsf/pzip/pzip.html> Later work by others, building on ‘pzip’ ,claims ‘100x’. > On 30 Dec 2024, at 00:44, Douglas McIlroy <douglas.mcilroy@dartmouth.edu> wrote: > > I can supply a copy if no one else has beaten me to it. > > Ron Hardin subsequently pushed the limit even further. Unfortunately, > I do not have a record of that work. > > Doug > > On Sat, Dec 28, 2024 at 9:54 PM Royce Williams <royce@techsolvency.com> wrote: >> >> Someone I know is seeking the original version of an internal Bell Labs memo from 1974 titled "Webster's Second on the Head of a Pin" by Morris and Thompson. The topic appears to be related to improving the speed of lookups or search. It's cited in a few papers as "Unpublished Technical Memo, Bell Laboratories, Murray Hill, NJ 1974." All I can find online is citations. Any leads appreciated! >> >> -- >> Royce Other links: This repository included ksh-93 sources Glen Fowlers’ downloads <https://web.archive.org/web/20130514131958/http://www2.research.att.com/~gsf/download/> Later AT&T Research page with Software downloads <https://web.archive.org/web/20090626002505/http://public.research.att.com/index.cfm?portal=19&h=55> THE AT&T AST OPENSOURCE SOFTWARE COLLECTION 2000 <https://www.usenix.org/legacy/publications/library/proceedings/usenix2000/freenix/full_papers/fowler/fowler.pdf> Github Repo for AST - I couldn’t make these compile <https://github.com/att/ast/tree/master> KSH93 <https://github.com/ksh93> -- Steve Jenkin, IT Systems and Design 0412 786 915 (+61 412 786 915) PO Box 38, Kippax ACT 2615, AUSTRALIA mailto:sjenkin@canb.auug.org.au http://members.tip.net.au/~sjenkin ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2024-12-29 13:44 ` [TUHS] " Douglas McIlroy 2024-12-30 21:13 ` sjenkin @ 2024-12-31 16:37 ` Chet Ramey via TUHS 2025-01-01 15:02 ` Douglas McIlroy 1 sibling, 1 reply; 18+ messages in thread From: Chet Ramey via TUHS @ 2024-12-31 16:37 UTC (permalink / raw) To: The Eunuchs Hysterical Society; +Cc: Douglas McIlroy [-- Attachment #1.1: Type: text/plain, Size: 699 bytes --] On 12/29/24 8:44 AM, Douglas McIlroy wrote: > I can supply a copy if no one else has beaten me to it. > > Ron Hardin subsequently pushed the limit even further. Unfortunately, > I do not have a record of that work. Along these same lines, does anyone on the list have a copy of "J. A. Reeds, /bin/sh: The biggest UNIX security Loophole, 11217-840302-04TM, AT&T Bell Laboratories, Murray Hill, NJ (1984)"? Years ago, in another lifetime, I wrote and asked him for a copy, but never got a reply. -- ``The lyf so short, the craft so long to lerne.'' - Chaucer ``Ars longa, vita brevis'' - Hippocrates Chet Ramey, UTech, CWRU chet@case.edu http://tiswww.cwru.edu/~chet/ [-- Attachment #2: OpenPGP digital signature --] [-- Type: application/pgp-signature, Size: 203 bytes --] ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2024-12-31 16:37 ` Chet Ramey via TUHS @ 2025-01-01 15:02 ` Douglas McIlroy 2025-01-01 18:11 ` Rik Farrow 0 siblings, 1 reply; 18+ messages in thread From: Douglas McIlroy @ 2025-01-01 15:02 UTC (permalink / raw) To: chet.ramey; +Cc: The Eunuchs Hysterical Society I have it and will try to scan it in the next few days. Bug me if it doesn't appear. Doug On Tue, Dec 31, 2024 at 11:37 AM Chet Ramey <chet.ramey@case.edu> wrote: > > On 12/29/24 8:44 AM, Douglas McIlroy wrote: > > I can supply a copy if no one else has beaten me to it. > > > > Ron Hardin subsequently pushed the limit even further. Unfortunately, > > I do not have a record of that work. > > Along these same lines, does anyone on the list have a copy of > > "J. A. Reeds, /bin/sh: The biggest UNIX security Loophole, > 11217-840302-04TM, AT&T Bell Laboratories, Murray Hill, NJ (1984)"? > > Years ago, in another lifetime, I wrote and asked him for a copy, but > never got a reply. > > -- > ``The lyf so short, the craft so long to lerne.'' - Chaucer > ``Ars longa, vita brevis'' - Hippocrates > Chet Ramey, UTech, CWRU chet@case.edu http://tiswww.cwru.edu/~chet/ ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2025-01-01 15:02 ` Douglas McIlroy @ 2025-01-01 18:11 ` Rik Farrow 2025-01-02 3:05 ` Douglas McIlroy 2025-01-02 14:22 ` Chet Ramey via TUHS 0 siblings, 2 replies; 18+ messages in thread From: Rik Farrow @ 2025-01-01 18:11 UTC (permalink / raw) To: Douglas McIlroy; +Cc: The Eunuchs Hysterical Society [-- Attachment #1: Type: text/plain, Size: 1518 bytes --] I wonder what Reeds meant. I know there are issues. For example, the 3B2 I administered for a while in the late 80s had multiple accounts with rsh, the restricted shell, as the login shell. That was okay, unless you used su and then had access to a root shell. HP/UX was way worse, with over 120 SUID shell scripts in the 90s. A much more interesting example of insecurity. But somehow, I'm guessing that's not what Reeds wrote about. Rik On Wed, Jan 1, 2025 at 8:02 AM Douglas McIlroy < douglas.mcilroy@dartmouth.edu> wrote: > I have it and will try to scan it in the next few days. Bug me if it > doesn't appear. > > Doug > > On Tue, Dec 31, 2024 at 11:37 AM Chet Ramey <chet.ramey@case.edu> wrote: > > > > On 12/29/24 8:44 AM, Douglas McIlroy wrote: > > > I can supply a copy if no one else has beaten me to it. > > > > > > Ron Hardin subsequently pushed the limit even further. Unfortunately, > > > I do not have a record of that work. > > > > Along these same lines, does anyone on the list have a copy of > > > > "J. A. Reeds, /bin/sh: The biggest UNIX security Loophole, > > 11217-840302-04TM, AT&T Bell Laboratories, Murray Hill, NJ (1984)"? > > > > Years ago, in another lifetime, I wrote and asked him for a copy, but > > never got a reply. > > > > -- > > ``The lyf so short, the craft so long to lerne.'' - Chaucer > > ``Ars longa, vita brevis'' - Hippocrates > > Chet Ramey, UTech, CWRU chet@case.edu > http://tiswww.cwru.edu/~chet/ > [-- Attachment #2: Type: text/html, Size: 2239 bytes --] ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2025-01-01 18:11 ` Rik Farrow @ 2025-01-02 3:05 ` Douglas McIlroy 2025-01-02 14:28 ` Chet Ramey via TUHS 2025-01-02 14:22 ` Chet Ramey via TUHS 1 sibling, 1 reply; 18+ messages in thread From: Douglas McIlroy @ 2025-01-02 3:05 UTC (permalink / raw) To: Rik Farrow; +Cc: TUHS main list I think $IFS ranks at the top of Jim's cabinet of horrors. For our multilevel-secure Unix (https://www.cs.dartmouth.edu/~doug/IX), he took almost everything out of the administrative shell, nosh (the no-shell shell), The classic /bin/sh was not endowed with any of the capabilities necessary to override Bell-LaPadula-Biba secrecy or integrity constraints. On Wed, Jan 1, 2025 at 1:11 PM Rik Farrow <rik@rikfarrow.com> wrote: > > I wonder what Reeds meant. I know there are issues. For example, the 3B2 I administered for a while in the late 80s had multiple accounts with rsh, the restricted shell, as the login shell. That was okay, unless you used su and then had access to a root shell. > > HP/UX was way worse, with over 120 SUID shell scripts in the 90s. A much more interesting example of insecurity. But somehow, I'm guessing that's not what Reeds wrote about. > > Rik > > > On Wed, Jan 1, 2025 at 8:02 AM Douglas McIlroy <douglas.mcilroy@dartmouth.edu> wrote: >> >> I have it and will try to scan it in the next few days. Bug me if it >> doesn't appear. >> >> Doug >> >> On Tue, Dec 31, 2024 at 11:37 AM Chet Ramey <chet.ramey@case.edu> wrote: >> > >> > On 12/29/24 8:44 AM, Douglas McIlroy wrote: >> > > I can supply a copy if no one else has beaten me to it. >> > > >> > > Ron Hardin subsequently pushed the limit even further. Unfortunately, >> > > I do not have a record of that work. >> > >> > Along these same lines, does anyone on the list have a copy of >> > >> > "J. A. Reeds, /bin/sh: The biggest UNIX security Loophole, >> > 11217-840302-04TM, AT&T Bell Laboratories, Murray Hill, NJ (1984)"? >> > >> > Years ago, in another lifetime, I wrote and asked him for a copy, but >> > never got a reply. >> > >> > -- >> > ``The lyf so short, the craft so long to lerne.'' - Chaucer >> > ``Ars longa, vita brevis'' - Hippocrates >> > Chet Ramey, UTech, CWRU chet@case.edu http://tiswww.cwru.edu/~chet/ ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2025-01-02 3:05 ` Douglas McIlroy @ 2025-01-02 14:28 ` Chet Ramey via TUHS 0 siblings, 0 replies; 18+ messages in thread From: Chet Ramey via TUHS @ 2025-01-02 14:28 UTC (permalink / raw) To: Douglas McIlroy, Rik Farrow; +Cc: TUHS main list [-- Attachment #1.1: Type: text/plain, Size: 435 bytes --] On 1/1/25 10:05 PM, Douglas McIlroy wrote: > I think $IFS ranks at the top of Jim's cabinet of horrors. Well, the Bourne shell's combination of importing IFS from the environment and then using it to split all words was particularly lethal. -- ``The lyf so short, the craft so long to lerne.'' - Chaucer ``Ars longa, vita brevis'' - Hippocrates Chet Ramey, UTech, CWRU chet@case.edu http://tiswww.cwru.edu/~chet/ [-- Attachment #2: OpenPGP digital signature --] [-- Type: application/pgp-signature, Size: 203 bytes --] ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2025-01-01 18:11 ` Rik Farrow 2025-01-02 3:05 ` Douglas McIlroy @ 2025-01-02 14:22 ` Chet Ramey via TUHS 2025-01-02 18:13 ` Rik Farrow 1 sibling, 1 reply; 18+ messages in thread From: Chet Ramey via TUHS @ 2025-01-02 14:22 UTC (permalink / raw) To: Rik Farrow, Douglas McIlroy; +Cc: The Eunuchs Hysterical Society [-- Attachment #1.1: Type: text/plain, Size: 787 bytes --] On 1/1/25 1:11 PM, Rik Farrow wrote: > I wonder what Reeds meant. I know there are issues. I've wondered myself. I am curious how many of these issues POSIX addresses (and bash, too, of course). > For example, the 3B2 I > administered for a while in the late 80s had multiple accounts with rsh, > the restricted shell, as the login shell. That was okay, unless you used su > and then had access to a root shell. That's an administrator problem. Part of setting up a restricted shell environment is creating a directory of necessary binaries and setting PATH appropriately. Chet -- ``The lyf so short, the craft so long to lerne.'' - Chaucer ``Ars longa, vita brevis'' - Hippocrates Chet Ramey, UTech, CWRU chet@case.edu http://tiswww.cwru.edu/~chet/ [-- Attachment #2: OpenPGP digital signature --] [-- Type: application/pgp-signature, Size: 203 bytes --] ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2025-01-02 14:22 ` Chet Ramey via TUHS @ 2025-01-02 18:13 ` Rik Farrow 2025-01-02 19:47 ` Chet Ramey via TUHS 0 siblings, 1 reply; 18+ messages in thread From: Rik Farrow @ 2025-01-02 18:13 UTC (permalink / raw) To: chet.ramey; +Cc: Douglas McIlroy, The Eunuchs Hysterical Society [-- Attachment #1: Type: text/plain, Size: 975 bytes --] On Thu, Jan 2, 2025 at 7:23 AM Chet Ramey <chet.ramey@case.edu> wrote: > On 1/1/25 1:11 PM, Rik Farrow wrote: > > For example, the 3B2 I > > administered for a while in the late 80s had multiple accounts with rsh, > > the restricted shell, as the login shell. That was okay, unless you used > su > > and then had access to a root shell. > > That's an administrator problem. Part of setting up a restricted shell > environment is creating a directory of necessary binaries and setting > PATH appropriately. > > Each of these special accounts did have a home directory with a .profile to set up the restricted environment, then run a shell script to perform some task as root. For example, logging in as 'backup' would run /user/backup/.profile and allow a non-privileged user to run a backup script as root. But typing "su backup" produced a root-owner shell without restrictions. You need to type "su - " to run the account's .profile script. Rik [-- Attachment #2: Type: text/html, Size: 1443 bytes --] ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2025-01-02 18:13 ` Rik Farrow @ 2025-01-02 19:47 ` Chet Ramey via TUHS 0 siblings, 0 replies; 18+ messages in thread From: Chet Ramey via TUHS @ 2025-01-02 19:47 UTC (permalink / raw) To: Rik Farrow; +Cc: Douglas McIlroy, The Eunuchs Hysterical Society [-- Attachment #1.1: Type: text/plain, Size: 1389 bytes --] On 1/2/25 1:13 PM, Rik Farrow wrote: > > > On Thu, Jan 2, 2025 at 7:23 AM Chet Ramey <chet.ramey@case.edu > <mailto:chet.ramey@case.edu>> wrote: > > On 1/1/25 1:11 PM, Rik Farrow wrote: > > For example, the 3B2 I > > administered for a while in the late 80s had multiple accounts with > rsh, > > the restricted shell, as the login shell. That was okay, unless you > used su > > and then had access to a root shell. > > That's an administrator problem. Part of setting up a restricted shell > environment is creating a directory of necessary binaries and setting > PATH appropriately. > > Each of these special accounts did have a home directory with a .profile to > set up the restricted environment, then run a shell script to perform some > task as root. For example, logging in as 'backup' would run /user/ > backup/.profile and allow a non-privileged user to run a backup script as root. > > But typing "su backup" produced a root-owner shell without restrictions. > You need to type "su - " to run the account's .profile script. OK, I thought you meant the other way, breaking out of a restricted environment. -- ``The lyf so short, the craft so long to lerne.'' - Chaucer ``Ars longa, vita brevis'' - Hippocrates Chet Ramey, UTech, CWRU chet@case.edu http://tiswww.cwru.edu/~chet/ [-- Attachment #2: OpenPGP digital signature --] [-- Type: application/pgp-signature, Size: 203 bytes --] ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2024-12-29 2:53 [TUHS] "Webster's Second on the Head of a Pin"? Royce Williams 2024-12-29 13:44 ` [TUHS] " Douglas McIlroy @ 2024-12-29 16:05 ` Douglas McIlroy 2025-03-10 22:55 ` James Johnston 2024-12-30 0:37 ` Warren Toomey via TUHS 2 siblings, 1 reply; 18+ messages in thread From: Douglas McIlroy @ 2024-12-29 16:05 UTC (permalink / raw) To: Royce Williams; +Cc: TUHS [-- Attachment #1: Type: text/plain, Size: 564 bytes --] I have sent a copy to Warren for the Unix archives. Doug On Sat, Dec 28, 2024 at 9:54 PM Royce Williams <royce@techsolvency.com> wrote: > > Someone I know is seeking the original version of an internal Bell Labs memo from 1974 titled "Webster's Second on the Head of a Pin" by Morris and Thompson. The topic appears to be related to improving the speed of lookups or search. It's cited in a few papers as "Unpublished Technical Memo, Bell Laboratories, Murray Hill, NJ 1974." All I can find online is citations. Any leads appreciated! > > -- > Royce [-- Attachment #2: PinheadWebster.pdf --] [-- Type: application/pdf, Size: 5881080 bytes --] ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2024-12-29 16:05 ` Douglas McIlroy @ 2025-03-10 22:55 ` James Johnston 2025-03-11 0:23 ` Douglas McIlroy 0 siblings, 1 reply; 18+ messages in thread From: James Johnston @ 2025-03-10 22:55 UTC (permalink / raw) To: Douglas McIlroy; +Cc: TUHS [-- Attachment #1: Type: text/plain, Size: 860 bytes --] Doug, do you know how much better Ziv-Lempel does? I'm guessing "a little bit"? On Mon, Mar 10, 2025 at 3:52 PM Douglas McIlroy < douglas.mcilroy@dartmouth.edu> wrote: > I have sent a copy to Warren for the Unix archives. > > Doug > > On Sat, Dec 28, 2024 at 9:54 PM Royce Williams <royce@techsolvency.com> > wrote: > > > > Someone I know is seeking the original version of an internal Bell Labs > memo from 1974 titled "Webster's Second on the Head of a Pin" by Morris and > Thompson. The topic appears to be related to improving the speed of lookups > or search. It's cited in a few papers as "Unpublished Technical Memo, Bell > Laboratories, Murray Hill, NJ 1974." All I can find online is citations. > Any leads appreciated! > > > > -- > > Royce > -- James D. (jj) Johnston Former Chief Scientist, Immersion Networks [-- Attachment #2: Type: text/html, Size: 1462 bytes --] ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2025-03-10 22:55 ` James Johnston @ 2025-03-11 0:23 ` Douglas McIlroy 2025-03-11 14:47 ` Jeff Johnson 0 siblings, 1 reply; 18+ messages in thread From: Douglas McIlroy @ 2025-03-11 0:23 UTC (permalink / raw) To: James Johnston; +Cc: TUHS Gnu lzip -9 got a 3.92 compression factor , while Morris-Thompson got 4.52. According to the lzip man page, lzip has integrity checks, which must take some space. It is also said to be a "simplified" L-Z, though the only simplification that is mentioned--bounding the size of the dictionary--can only happen on much bigger files than Webster. If you still wonder how well "pure" L-Z does, I'll be happy to try your favorite implementation. It did not surprise me that lzip lost to M-T, for it has to discover over and over again that the dictionary is lexicographically ordered--a fact that gives M-T most of its leverage. The dictionary is definitely not generated by a Markov process! Doug On Mon, Mar 10, 2025 at 6:56 PM James Johnston <audioskeptic@gmail.com> wrote: > > Doug, do you know how much better Ziv-Lempel does? I'm guessing "a little bit"? > > On Mon, Mar 10, 2025 at 3:52 PM Douglas McIlroy <douglas.mcilroy@dartmouth.edu> wrote: >> >> I have sent a copy to Warren for the Unix archives. >> >> Doug >> >> On Sat, Dec 28, 2024 at 9:54 PM Royce Williams <royce@techsolvency.com> wrote: >> > >> > Someone I know is seeking the original version of an internal Bell Labs memo from 1974 titled "Webster's Second on the Head of a Pin" by Morris and Thompson. The topic appears to be related to improving the speed of lookups or search. It's cited in a few papers as "Unpublished Technical Memo, Bell Laboratories, Murray Hill, NJ 1974." All I can find online is citations. Any leads appreciated! >> > >> > -- >> > Royce > > > > -- > James D. (jj) Johnston > > Former Chief Scientist, Immersion Networks ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2025-03-11 0:23 ` Douglas McIlroy @ 2025-03-11 14:47 ` Jeff Johnson 2025-03-12 12:41 ` Douglas McIlroy 0 siblings, 1 reply; 18+ messages in thread From: Jeff Johnson @ 2025-03-11 14:47 UTC (permalink / raw) Cc: TUHS As far as getting maximum compression from lzip, `lzip -9 -s 512Mi` is usually the preferred invocation. I think the default dictionary size at -9 is 64MiB, but that's not that relevant I guess, unless we are comparing different methods and trying to see about what ratios different algorithms get at similar memory usage. -- Jeffrey H. Johnson trnsz@pobox.com On Mon, Mar 10, 2025, at 8:23 PM, Douglas McIlroy wrote: > Gnu lzip -9 got a 3.92 compression factor , while Morris-Thompson got 4.52. -- Jeffrey H. Johnson trnsz@pobox.com On Mon, Mar 10, 2025, at 8:23 PM, Douglas McIlroy wrote: > Gnu lzip -9 got a 3.92 compression factor , while Morris-Thompson got 4.52. ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2025-03-11 14:47 ` Jeff Johnson @ 2025-03-12 12:41 ` Douglas McIlroy 0 siblings, 0 replies; 18+ messages in thread From: Douglas McIlroy @ 2025-03-12 12:41 UTC (permalink / raw) To: Jeff Johnson; +Cc: TUHS [-- Attachment #1: Type: text/plain, Size: 981 bytes --] Thanks for the advice. I somehow had inferred from the man page that 512M was the default. In any event, it doesn't move the needle on compression ratio. Doug On Tue, Mar 11, 2025 at 10:47 AM Jeff Johnson <trnsz@pobox.com> wrote: > As far as getting maximum compression from lzip, `lzip -9 -s 512Mi` > is usually the preferred invocation. I think the default dictionary > size at -9 is 64MiB, but that's not that relevant I guess, unless > we are comparing different methods and trying to see about what > ratios different algorithms get at similar memory usage. > > -- > Jeffrey H. Johnson > trnsz@pobox.com > > On Mon, Mar 10, 2025, at 8:23 PM, Douglas McIlroy wrote: > > Gnu lzip -9 got a 3.92 compression factor , while Morris-Thompson got > 4.52. > > -- > Jeffrey H. Johnson > trnsz@pobox.com > > On Mon, Mar 10, 2025, at 8:23 PM, Douglas McIlroy wrote: > > Gnu lzip -9 got a 3.92 compression factor , while Morris-Thompson got > 4.52. > [-- Attachment #2: Type: text/html, Size: 1453 bytes --] ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2024-12-29 2:53 [TUHS] "Webster's Second on the Head of a Pin"? Royce Williams 2024-12-29 13:44 ` [TUHS] " Douglas McIlroy 2024-12-29 16:05 ` Douglas McIlroy @ 2024-12-30 0:37 ` Warren Toomey via TUHS 2024-12-30 2:07 ` Royce Williams 2 siblings, 1 reply; 18+ messages in thread From: Warren Toomey via TUHS @ 2024-12-30 0:37 UTC (permalink / raw) To: Royce Williams; +Cc: tuhs On Sat, Dec 28, 2024 at 05:53:48PM -0900, Royce Williams wrote: > Someone I know is seeking the original version of an internal Bell Labs > memo from 1974 titled "Webster's Second on the Head of a Pin" by Morris > and Thompson. The topic appears to be related to improving the speed of > lookups or search. It's cited in a few papers as "Unpublished Technical > Memo, Bell Laboratories, Murray Hill, NJ 1974." All I can find online > is citations. Any leads appreciated! Doug McIlroy sent me a copy, it's now here: https://www.tuhs.org/Archive/Documentation/TechReports/Bell_Labs/PinheadWebster.pdf Thanks Doug! Warren ^ permalink raw reply [flat|nested] 18+ messages in thread
* [TUHS] Re: "Webster's Second on the Head of a Pin"? 2024-12-30 0:37 ` Warren Toomey via TUHS @ 2024-12-30 2:07 ` Royce Williams 0 siblings, 0 replies; 18+ messages in thread From: Royce Williams @ 2024-12-30 2:07 UTC (permalink / raw) To: tuhs [-- Attachment #1: Type: text/plain, Size: 1859 bytes --] On Sun, Dec 29, 2024 at 3:37 PM Warren Toomey <wkt@tuhs.org> wrote: > On Sat, Dec 28, 2024 at 05:53:48PM -0900, Royce Williams wrote: > > Someone I know is seeking the original version of an internal Bell > Labs > > memo from 1974 titled "Webster's Second on the Head of a Pin" by > Morris > > and Thompson. The topic appears to be related to improving the speed > of > > lookups or search. It's cited in a few papers as "Unpublished > Technical > > Memo, Bell Laboratories, Murray Hill, NJ 1974." All I can find online > > is citations. Any leads appreciated! > > Doug McIlroy sent me a copy, it's now here: > > > https://www.tuhs.org/Archive/Documentation/TechReports/Bell_Labs/PinheadWebster.pdf > > Thanks Doug! > And many thanks from me and my colleague as well, Doug! For future searchers, what follows is selected (unique) front matter from the memo, rewrapped slightly for Mailman width. Title - Webster's Second on the Head of a Pin Date - July 15, 1974 TM - 74-1271-13 Other keywords - words, text compression Author Location Extension Robert Morris MH 2C-524 3878 Ken Thompson MH 2C-523 2394 Charging case - 39199 Filing Case - 39199-11 ABSTRACT We used the list of words from Webster's Second Unabridged Dictionary (without definitions) as a test case for special purpose text compression techniques. We compressed it by a factor of 4.52 to 1. The 234,932 words originally occupied 2,486,781 bytes and were compressed into 549,388 bytes. The size of the decoding program is 1356 bytes. The initial characters of a word that agreed with the initial characters of the previous word were dropped and replaced by a code. Common suffixes were also coded. Finally, a variable-length code was used. Pages Text 6 Other 0 Total 6 -- Royce [-- Attachment #2: Type: text/html, Size: 2641 bytes --] ^ permalink raw reply [flat|nested] 18+ messages in thread
end of thread, other threads:[~2025-03-12 12:41 UTC | newest] Thread overview: 18+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2024-12-29 2:53 [TUHS] "Webster's Second on the Head of a Pin"? Royce Williams 2024-12-29 13:44 ` [TUHS] " Douglas McIlroy 2024-12-30 21:13 ` sjenkin 2024-12-31 16:37 ` Chet Ramey via TUHS 2025-01-01 15:02 ` Douglas McIlroy 2025-01-01 18:11 ` Rik Farrow 2025-01-02 3:05 ` Douglas McIlroy 2025-01-02 14:28 ` Chet Ramey via TUHS 2025-01-02 14:22 ` Chet Ramey via TUHS 2025-01-02 18:13 ` Rik Farrow 2025-01-02 19:47 ` Chet Ramey via TUHS 2024-12-29 16:05 ` Douglas McIlroy 2025-03-10 22:55 ` James Johnston 2025-03-11 0:23 ` Douglas McIlroy 2025-03-11 14:47 ` Jeff Johnson 2025-03-12 12:41 ` Douglas McIlroy 2024-12-30 0:37 ` Warren Toomey via TUHS 2024-12-30 2:07 ` Royce Williams
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