Thread: IBM releases 500 patents
IBM has just announced they are waving all rights and providing access to 500 patents. In the list of 500 there are several that relate RDBMS and query optimizations, it may be worth a look. http://www.ibm.com/news/us/en/2005/01/patents.html -- Darcy Buskermolen Wavefire Technologies Corp. ph: 250.717.0200 fx: 250.763.1759 http://www.wavefire.com
Darcy Buskermolen wrote: >IBM has just announced they are waving all rights and providing access to 500 >patents. In the list of 500 there are several that relate RDBMS and query >optimizations, it may be worth a look. > > >http://www.ibm.com/news/us/en/2005/01/patents.html > > Except in the event of a lawsuit. J -- Command Prompt, Inc., home of Mammoth PostgreSQL - S/ODBC and S/JDBC Postgresql support, programming shared hosting and dedicated hosting. +1-503-667-4564 - jd@commandprompt.com - http://www.commandprompt.com PostgreSQL Replicator -- production quality replication for PostgreSQL
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On January 11, 2005 08:13 am, you wrote: > Darcy Buskermolen wrote: > >IBM has just announced they are waving all rights and providing access to > > 500 patents. In the list of 500 there are several that relate RDBMS and > > query optimizations, it may be worth a look. > > > > > >http://www.ibm.com/news/us/en/2005/01/patents.html > > Except in the event of a lawsuit. > > > J I've read the full patent release document (http://www.ibm.com/ibm/licensing/patents/pledgedpatents.pdf) and from what I see there, IBM has made a commitment not to defend the patentents against anybody who uses them in a supported OSS licensing scheme (those found on opensourcelicence.org) -- Darcy Buskermolen Wavefire Technologies Corp. ph: 250.717.0200 fx: 250.763.1759 http://www.wavefire.com
On Tue, Jan 11, 2005 at 08:13:01AM -0800, Joshua D. Drake wrote: > Darcy Buskermolen wrote: > > >IBM has just announced they are waving all rights and providing access to > >500 patents. In the list of 500 there are several that relate RDBMS and > >query optimizations, it may be worth a look. > > > >http://www.ibm.com/news/us/en/2005/01/patents.html > > Except in the event of a lawsuit. And derived closed-source products like SRA's or CMD's Postgres offerings would not be able to include whatever is covered by the patents. -- Alvaro Herrera (<alvherre[@]dcc.uchile.cl>) "La rebeldía es la virtud original del hombre" (Arthur Schopenhauer)
On January 11, 2005 08:32 am, Darcy Buskermolen wrote: > On January 11, 2005 08:13 am, you wrote: > > Darcy Buskermolen wrote: > > >IBM has just announced they are waving all rights and providing access > > > to 500 patents. In the list of 500 there are several that relate RDBMS > > > and query optimizations, it may be worth a look. > > > > > > > > >http://www.ibm.com/news/us/en/2005/01/patents.html > > > > Except in the event of a lawsuit. > > > > > > J > > I've read the full patent release document > (http://www.ibm.com/ibm/licensing/patents/pledgedpatents.pdf) and from what > I see there, IBM has made a commitment not to defend the patentents against > anybody who uses them in a supported OSS licensing scheme (those found on > opensourcelicence.org) Correction, make that http://opensource.org -- Darcy Buskermolen Wavefire Technologies Corp. ph: 250.717.0200 fx: 250.763.1759 http://www.wavefire.com
On January 11, 2005 08:34 am, Alvaro Herrera wrote: > On Tue, Jan 11, 2005 at 08:13:01AM -0800, Joshua D. Drake wrote: > > Darcy Buskermolen wrote: > > >IBM has just announced they are waving all rights and providing access > > > to 500 patents. In the list of 500 there are several that relate RDBMS > > > and query optimizations, it may be worth a look. > > > > > >http://www.ibm.com/news/us/en/2005/01/patents.html > > > > Except in the event of a lawsuit. > > And derived closed-source products like SRA's or CMD's Postgres > offerings would not be able to include whatever is covered by the patents. In that pg uses a BSD license, which is supported by OSO and which allows for: Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. I can't see binary modified distros like those offred by CP and SRA would be breaking this license. -- Darcy Buskermolen Wavefire Technologies Corp. ph: 250.717.0200 fx: 250.763.1759 http://www.wavefire.com
Darcy Buskermolen wrote: > On January 11, 2005 08:34 am, Alvaro Herrera wrote: > > On Tue, Jan 11, 2005 at 08:13:01AM -0800, Joshua D. Drake wrote: > > > Darcy Buskermolen wrote: > > > >IBM has just announced they are waving all rights and providing access > > > > to 500 patents. In the list of 500 there are several that relate RDBMS > > > > and query optimizations, it may be worth a look. > > > > > > > >http://www.ibm.com/news/us/en/2005/01/patents.html > > > > > > Except in the event of a lawsuit. > > > > And derived closed-source products like SRA's or CMD's Postgres > > offerings would not be able to include whatever is covered by the patents. > > In that pg uses a BSD license, which is supported by OSO and which allows for: > > Redistribution and use in source and binary forms, with or without > modification, are permitted provided that the following conditions are met: > > * Redistributions of source code must retain the above copyright notice, this > list of conditions and the following disclaimer. > > * Redistributions in binary form must reproduce the above copyright notice, > this list of conditions and the following disclaimer in the documentation > and/or other materials provided with the distribution. > > > I can't see binary modified distros like those offred by CP and SRA would be > breaking this license. The new distros have their own license on top of the existing one that gives ownership to the company distributing it and requiring payment for those using it, so they have a different license than BSD. -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 359-1001+ If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania19073
They probaly released the informix database patents. This is pertinent to us as several of them were interesting implementations of things like the function manager. --elein On Tue, Jan 11, 2005 at 08:04:48AM -0800, Darcy Buskermolen wrote: > IBM has just announced they are waving all rights and providing access to 500 > patents. In the list of 500 there are several that relate RDBMS and query > optimizations, it may be worth a look. > > > http://www.ibm.com/news/us/en/2005/01/patents.html > -- > Darcy Buskermolen > Wavefire Technologies Corp. > ph: 250.717.0200 > fx: 250.763.1759 > http://www.wavefire.com > > ---------------------------(end of broadcast)--------------------------- > TIP 5: Have you checked our extensive FAQ? > > http://www.postgresql.org/docs/faqs/FAQ.html
On Tue, Jan 11, 2005 at 10:33:44 -0800, Elein Mustain <elein@tulip.norcov.com> wrote: > They probaly released the informix database patents. > This is pertinent to us as several of them were interesting > implementations of things like the function manager. From what I read of this, the way they released the patents isn't completely compatible with BSD licenses.
You can get the list of patents from here: http://www-106.ibm.com/developerworks/blogs/dw_blog_comments.jspa?blog=384&entry=69779 -----Original Message----- From: Bruno Wolff III [mailto:bruno@wolff.to] Sent: Friday, January 14, 2005 10:29 AM To: Elein Mustain Cc: Darcy Buskermolen; pgsql-hackers@postgresql.org Subject: Re: [HACKERS] IBM releases 500 patents On Tue, Jan 11, 2005 at 10:33:44 -0800, Elein Mustain <elein@tulip.norcov.com> wrote: > They probaly released the informix database patents. > This is pertinent to us as several of them were interesting > implementations of things like the function manager. From what I read of this, the way they released the patents isn't completely compatible with BSD licenses. ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster
On Fri, Jan 14, 2005 at 10:28:52AM -0600, Bruno Wolff III wrote: > On Tue, Jan 11, 2005 at 10:33:44 -0800, > Elein Mustain <elein@tulip.norcov.com> wrote: > > They probaly released the informix database patents. > > This is pertinent to us as several of them were interesting > > implementations of things like the function manager. > > From what I read of this, the way they released the patents isn't completely > compatible with BSD licenses. Is the only concern the commercialized offerings of PostgreSQL? It seems that commercial entities could either negotiate terms with IBM or help maintain a 'patent-free' branch of PostgreSQL. Yes, sub-optimal and a good amount of work, but depending on what's to be gained by utilizing some of the patents it might still be better for PostgreSQL overall. I don't know how useful the IP in the patents is, but I'd hate to see it dismissed out-of-hand because of licensing difficulties that could be overcome. -- Jim C. Nasby, Database Consultant decibel@decibel.org Give your computer some brain candy! www.distributed.net Team #1828 Windows: "Where do you want to go today?" Linux: "Where do you want to go tomorrow?" FreeBSD: "Are you guys coming, or what?"
On Tue, 2005-01-11 at 08:04 -0800, Darcy Buskermolen wrote: > IBM has just announced they are waving all rights and providing access to 500 > patents. In the list of 500 there are several that relate RDBMS and query > optimizations, it may be worth a look. FYI, IBM has applied for a patent on ARC (AFAICS the patent application is still pending, although the USPTO site is a little hard to grok): http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220040098541%22.PGNR.&OS=DN/20040098541&RS=DN/20040098541 -Neil
Neil Conway <neilc@samurai.com> writes: > FYI, IBM has applied for a patent on ARC (AFAICS the patent application > is still pending, although the USPTO site is a little hard to grok): > http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220040098541%22.PGNR.&OS=DN/20040098541&RS=DN/20040098541 Ugh. We could hope that the patent wouldn't be granted, but I think it unlikely, unless Jan is aware of prior art (like a publication predating the filing date). I fear we'll have to change or remove that code. regards, tom lane
On Mon, 2005-01-17 at 01:15 -0500, Tom Lane wrote: > Neil Conway <neilc@samurai.com> writes: > > FYI, IBM has applied for a patent on ARC (AFAICS the patent application > > is still pending, although the USPTO site is a little hard to grok): > > > http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220040098541%22.PGNR.&OS=DN/20040098541&RS=DN/20040098541 On Mon, 2005-01-17 at 01:15 -0500, Tom Lane wrote: > I fear we'll have to change or remove > that code. At very least, ARC should not be further mentioned in any press release or beta history files until we resolve where we are. There'll be less need for a retraction if the buffer strategy is not publicised. The code separation of bufmgr.c and freelist.c means that changes can be done later without too much of a problem. Any required changes can be made under the covers without external recall-notices or such. Well, considering the BufMgrLock problems, it was likely that some changes would need to be be made to that algorithm anyway. ARC may be optimal in lab tests, but I'm beginning to think that it's not optimal in multi-processing environments. It also takes no direct account of the workload it is being asked to support, so ISTM that we should be able to use workload hints, along the lines of StrategyHintVacuum, to get a more responsive algorithm suited specifically to PostgreSQL - which would be harder to claim rights on. -- Best Regards, Simon Riggs
On 1/17/2005 1:15 AM, Tom Lane wrote: > Neil Conway <neilc@samurai.com> writes: >> FYI, IBM has applied for a patent on ARC (AFAICS the patent application >> is still pending, although the USPTO site is a little hard to grok): > >> http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220040098541%22.PGNR.&OS=DN/20040098541&RS=DN/20040098541 > > Ugh. We could hope that the patent wouldn't be granted, but I think > it unlikely, unless Jan is aware of prior art (like a publication > predating the filing date). I fear we'll have to change or remove > that code. > > regards, tom lane Unfortunately no. The document that inspired me to adapt ARC for PostgreSQL is from the USENIX File & Storage Technologies Conference (FAST), March 31, 2003, San Francisco, CA. I am seriously concerned about this and think we should not knowingly release code that is possibly infringing a patent. If we need a different cache algorithm again, we might want to yank out the ARC part right away now and work on another one for 8.1. Jan -- #======================================================================# # It's easier to get forgiveness for being wrong than for being right. # # Let's break this rule - forgive me. # #================================================== JanWieck@Yahoo.com #
Jan Wieck wrote: > On 1/17/2005 1:15 AM, Tom Lane wrote: > > Neil Conway <neilc@samurai.com> writes: > >> FYI, IBM has applied for a patent on ARC (AFAICS the patent application > >> is still pending, although the USPTO site is a little hard to grok): > > > >> http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220040098541%22.PGNR.&OS=DN/20040098541&RS=DN/20040098541 > > > > Ugh. We could hope that the patent wouldn't be granted, but I think > > it unlikely, unless Jan is aware of prior art (like a publication > > predating the filing date). I fear we'll have to change or remove > > that code. > > > > regards, tom lane > > Unfortunately no. The document that inspired me to adapt ARC for > PostgreSQL is from the USENIX File & Storage Technologies Conference > (FAST), March 31, 2003, San Francisco, CA. Oh, OK. Good news! > I am seriously concerned about this and think we should not knowingly > release code that is possibly infringing a patent. > > If we need a different cache algorithm again, we might want to yank out > the ARC part right away now and work on another one for 8.1. If you want to poke around for 2 hours, I bet you wil find more patent infringements. And not looking doesn't protect you from patent violations. What is the point of removing this one. Just because Neil did some legwork. Anyone could do some legwork and find some in any software, I bet. -- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610) 359-1001+ If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania19073
>If you want to poke around for 2 hours, I bet you wil find more patent >infringements. And not looking doesn't protect you from patent >violations. What is the point of removing this one. Just because Neil >did some legwork. Anyone could do some legwork and find some in any >software, I bet. > > Well from one perspective... Digging for patent infringement is expensive just look at the SCO suit. However, this is a public list. We have just admitted that we knowingly may infringe upon an IBM patent. That really is a different thing than, "We have some really smart people that came up with something, "like" this other technology". The reality I would bet is that IBM could give a flying roosters butt whether or not PostgreSQL infringes on their patents. However they will care very much, if Fujitsu or SRA does and we (the community) may have insured that. Sincerely, Joshua D. Drake -- Command Prompt, Inc., home of Mammoth PostgreSQL - S/ODBC and S/JDBC Postgresql support, programming shared hosting and dedicated hosting. +1-503-667-4564 - jd@commandprompt.com - http://www.commandprompt.com PostgreSQL Replicator -- production quality replication for PostgreSQL
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On Mon, 2005-01-17 at 12:15 -0800, Joshua D. Drake wrote: > We have just admitted that we knowingly may infringe upon > an IBM patent. That really is a different thing than, > "We have some really smart people that came up with something, > "like" this other technology". The code is clear that it implements the "Adaptive Replacement Cache", which is an algorithm proposed by IBM; the code probably references some IBM papers on the topic -- and if not, discussions of ARC on -hackers certainly do. I don't see how there could be any reasonable grounds for arguing that, prior to this thread, we just "came up with something really, really similar". -Neil
On Mon, 17 Jan 2005, Joshua D. Drake wrote: > >> If you want to poke around for 2 hours, I bet you wil find more patent >> infringements. And not looking doesn't protect you from patent >> violations. What is the point of removing this one. Just because Neil >> did some legwork. Anyone could do some legwork and find some in any >> software, I bet. >> > Well from one perspective... Digging for patent infringement > is expensive just look at the SCO suit. However, this is a > public list. > > We have just admitted that we knowingly may infringe upon > an IBM patent. That really is a different thing than, > "We have some really smart people that came up with something, > "like" this other technology". > > The reality I would bet is that IBM could give a flying roosters > butt whether or not PostgreSQL infringes on their patents. However > they will care very much, if Fujitsu or SRA does and we (the > community) may have insured that. As one famous chicken put it 'the sky is falling, the sky is falling' ... or, in our case "a patent is pending, a patent is pending' ... there is no patent, there might never be a patent ... instead of panic'ng over something that may nevr happen, why not just keep an eye on the patent process itself and see wher it goes. It might takes months yet to go anywhere ... lots of time for us to come up with an alternate ... ---- Marc G. Fournier Hub.Org Networking Services (http://www.hub.org) Email: scrappy@hub.org Yahoo!: yscrappy ICQ: 7615664
On Monday 17 January 2005 15:15, Joshua D. Drake wrote:
> >If you want to poke around for 2 hours, I bet you wil find more patent
> >infringements. And not looking doesn't protect you from patent
> >violations. What is the point of removing this one. Just because Neil
> >did some legwork. Anyone could do some legwork and find some in any
> >software, I bet.
<snip>
>
> We have just admitted that we knowingly may infringe upon
> an IBM patent. That really is a different thing than,
> "We have some really smart people that came up with something,
> "like" this other technology".
>
Well, if I am reading that right, IBM doesn't actually have a patent on the
technology yet, so we aren't releasing code that infringes on a patent as it
remains to be seen whether or not the technology will be deemed patentable or
if it is considered a natural evolution of other technology.
That said a little bit of googling doesn't look promising for finding prior
art, though that doesn't mean a case against can't be argued.
> The reality I would bet is that IBM could give a flying roosters
> butt whether or not PostgreSQL infringes on their patents. However
> they will care very much, if Fujitsu or SRA does and we (the
> community) may have insured that.
>
Well, I don't know if they will care "very much", but it seems likely thier
lawyers would contact people with ceast and desist letters which, imho would
probably force the community to abondon any version of software with the arc
implementation. Of course the genesis of all this was IBM opening these
patents for use by open source projects, so if a scheme could be worked out
leaving both an arc implementation and an lru implementation in place, with
the understanding that the arc implementation would have issues for
commercial distribution, it might be possible to keep both. I also think
that, as long as the software is being sold with an open source license (ie.
where companies are basically reselling the community version of postgresql,
or selling with another osi approved license) they should be in the clear.
If folks are really concerned, there are a few things that should/could be
done:
1) go back and see if there is a /. article about this (is it even possible
there isn't?) and see if anyone else brought up these concerns. If not, post
some of these questions and see what kind of response you get.
2) There is a group (I think linked from larry lessigs website) that searches
for prior art for software patents. You might bring this case to them and see
if they have any interest in looking into it.
3) See if you can find any other software packages (preferably commercial)
that implement arc tech and see if they have looked into the issue.
4) Have someone from the community contact IBM with some of these questions (a
good candidate would be someone associated with the foundation) and see what
thier take is. I wouldn't expect much from this but you never know.
--
Robert Treat
Build A Brighter Lamp :: Linux Apache {middleware} PostgreSQL
On Mon, 17 Jan 2005 15:07:30 -0500, Bruce Momjian wrote: > Jan Wieck wrote: >> On 1/17/2005 1:15 AM, Tom Lane wrote: >> > Neil Conway <neilc@samurai.com> writes: >> >> FYI, IBM has applied for a patent on ARC (AFAICS the patent >> >> application is still pending, although the USPTO site is a little >> >> hard to grok): >> > >> >> http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220040098541%22.PGNR.&OS=DN/20040098541&RS=DN/20040098541 >> > >> > Ugh. We could hope that the patent wouldn't be granted, but I think >> > it unlikely, unless Jan is aware of prior art (like a publication >> > predating the filing date). I fear we'll have to change or remove >> > that code. >> > >> > regards, tom lane >> >> Unfortunately no. The document that inspired me to adapt ARC for >> PostgreSQL is from the USENIX File & Storage Technologies Conference >> (FAST), March 31, 2003, San Francisco, CA. > > Oh, OK. Good news! > >> I am seriously concerned about this and think we should not knowingly >> release code that is possibly infringing a patent. >> >> If we need a different cache algorithm again, we might want to yank out >> the ARC part right away now and work on another one for 8.1. > > If you want to poke around for 2 hours, I bet you wil find more patent > infringements. And not looking doesn't protect you from patent > violations. Not looking does protect you from a "willful patent violation lawsuit", as I understand it. Personally I'd be surprised if any commercial entity wanted to take the risk that 15 years down the track the patent is granted retrospectively and that IBM wouldn't come knocking. Especially since 8.0 is now out in the field with the ARC code. "Friends don't let friends read patents". Cheers, Anand -- linux.conf.au 2005 - http://lca2005.linux.org.au/ - Birthplace of Tux April 18th to 23rd - http://lca2005.linux.org.au/ - LINUX Canberra, Australia - http://lca2005.linux.org.au/ - Get bitten!
Tom Lane wrote: > Neil Conway <neilc@samurai.com> writes: > >>FYI, IBM has applied for a patent on ARC (AFAICS the patent application >>is still pending, although the USPTO site is a little hard to grok): > > >>http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220040098541%22.PGNR.&OS=DN/20040098541&RS=DN/20040098541 > > > Ugh. We could hope that the patent wouldn't be granted, but I think > it unlikely, unless Jan is aware of prior art (like a publication > predating the filing date). I fear we'll have to change or remove > that code. > > regards, tom lane > > ---------------------------(end of broadcast)--------------------------- > TIP 7: don't forget to increase your free space map settings > And what about "CAR: Clock with Adaptive Replacement"? I found something here: http://www.cs.duke.edu/csl/usenix/04fast/tech/bansal.html Is it worth investigating? best wishes, marian
On Thu, 31 Mar 2005, Marian POPESCU wrote: > Tom Lane wrote: > > Neil Conway <neilc@samurai.com> writes: > > > >>FYI, IBM has applied for a patent on ARC (AFAICS the patent application > >>is still pending, although the USPTO site is a little hard to grok): > > > > > >>http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220040098541%22.PGNR.&OS=DN/20040098541&RS=DN/20040098541 > > > > > > Ugh. We could hope that the patent wouldn't be granted, but I think > > it unlikely, unless Jan is aware of prior art (like a publication > > predating the filing date). I fear we'll have to change or remove > > that code. > > > > regards, tom lane > > > > ---------------------------(end of broadcast)--------------------------- > > TIP 7: don't forget to increase your free space map settings > > > And what about "CAR: Clock with Adaptive Replacement"? > > I found something here: > http://www.cs.duke.edu/csl/usenix/04fast/tech/bansal.html > > Is it worth investigating? Firstly, it clearly states that it is a derivation of ARC. Secondly, one of the authors is from IBM. Implementing this algorithm will probably cause the same problem as the implementation of ARC. > > best wishes, > marian Thanks, Gavin
Gavin Sherry wrote: > On Thu, 31 Mar 2005, Marian POPESCU wrote: > > >>Tom Lane wrote: >> >>>Neil Conway <neilc@samurai.com> writes: >>> >>> >>>>FYI, IBM has applied for a patent on ARC (AFAICS the patent application >>>>is still pending, although the USPTO site is a little hard to grok): >>> >>> >>>>http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220040098541%22.PGNR.&OS=DN/20040098541&RS=DN/20040098541 >>> >>> >>>Ugh. We could hope that the patent wouldn't be granted, but I think >>>it unlikely, unless Jan is aware of prior art (like a publication >>>predating the filing date). I fear we'll have to change or remove >>>that code. >>> >>> regards, tom lane >>> >>>---------------------------(end of broadcast)--------------------------- >>>TIP 7: don't forget to increase your free space map settings >>> >> >>And what about "CAR: Clock with Adaptive Replacement"? >> >>I found something here: >>http://www.cs.duke.edu/csl/usenix/04fast/tech/bansal.html >> >>Is it worth investigating? > > > Firstly, it clearly states that it is a derivation of ARC. Secondly, one > of the authors is from IBM. Implementing this algorithm will probably > cause the same problem as the implementation of ARC. > > >>best wishes, >>marian > > > Thanks, > > Gavin > > ---------------------------(end of broadcast)--------------------------- > TIP 4: Don't 'kill -9' the postmaster > There is also LIRS: http://www.cs.wm.edu/~sjiang/lirs.htm Interesting?