Обсуждение: Postgres Process in Kernel Mode?
<div class="Section1"><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial">Hello,</span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial"> </span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial">I’m new in postgres SQL and I have some questions about the space where postgres process run.</span></font><pclass="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial"> </span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial"> </span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial">1-Can any body say me what libs use postgres for make system calls, for example LIBC? </span></font><pclass="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial">2-Can any body talk me if some postgres process can run in Linux kernel space? </span></font><pclass="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial">3- Some body knows if exist some projects that ports postgres process on Linux kernel space.</span></font><pclass="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial"> </span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial"> </span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial">I was read some source code of postgres, like, </span></font><p class="MsoNormal"><font face="Arial"size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial">Postgres.C and others…</span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB"style="font-size: 10.0pt;font-family:Arial"> </span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial">I was found C instructions like Printf, that’s prohibitive for Linux kernel applications, for examplein kernel mode we use printk.</span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial"> </span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial">I suppose that postgres are ported in a user space only. I’m Ok?</span></font><p class="MsoNormal"><fontface="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial"> </span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial">Thanks </span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial">Moises</span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial"> </span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial"> </span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial"> </span></font><p class="MsoNormal"><font face="Arial" size="2"><span lang="EN-GB" style="font-size: 10.0pt;font-family:Arial">- </span></font></div>
moises wrote: > 1-Can any body say me what libs use postgres for make system calls, for > example LIBC? libc and a lot others. > 2-Can any body talk me if some postgres process can run in Linux kernel > space? No. > 3- Some body knows if exist some projects that ports postgres process on > Linux kernel space. No that we've heard lately. (But I remember a guy with a .cu domain asking not long ago, maybe it was you.) > I was found C instructions like Printf, that's prohibitive for Linux kernel > applications, for example in kernel mode we use printk. That's because Postgres is a user-space program and there are no intentions to change that. > I suppose that postgres are ported in a user space only. I'm Ok? Yes. If you prefer spanish, I suggest you subscribe to the pgsql-es-ayuda list. There is at least one Postgres hacker there. -- Alvaro Herrera http://www.CommandPrompt.com/ The PostgreSQL Company - Command Prompt, Inc.
moises@cedaivc.co.cu ("moises") writes: > <html xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns="http://www.w3.org/TR/REC-html40"> > > <head> > <meta http-equiv=Content-Type content="text/html; charset=us-ascii"> > <meta name=Generator content="Microsoft Word 11 (filtered medium)"> > <style> > <!-- > /* Style Definitions */ > p.MsoNormal, li.MsoNormal, div.MsoNormal > {margin:0cm; > margin-bottom:.0001pt; > font-size:12.0pt; > font-family:"Times New Roman";} > a:link, span.MsoHyperlink > {color:blue; > text-decoration:underline;} > a:visited, span.MsoHyperlinkFollowed > {color:purple; > text-decoration:underline;} > span.EstiloCorreo17 > {mso-style-type:personal-compose; > font-family:Arial; > color:windowtext;} > @page Section1 > {size:595.3pt 841.9pt; > margin:70.85pt 3.0cm 70.85pt 3.0cm;} > div.Section1 > {page:Section1;} > --> > </style> > > </head> > > <body lang=ES link=blue vlink=purple> > > <div class=Section1> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'>Hello,<o:p></o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'><o:p> </o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'>I’m new in postgres SQL and I have some > questions about the space where postgres process run.<o:p></o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'><o:p> </o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'><o:p> </o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'>1-Can any body say me what libs use postgres for make > system calls, for example LIBC? <o:p></o:p></span></font></p> You can easily determine this yourself using ldd. The answer will vary depending on what options you use when compiling it. > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'>2-Can any body talk me if some postgres process can > run in Linux kernel space? <o:p></o:p></span></font></p> Yes, it doesn't. > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'>3- Some body knows if exist some projects that ports postgres > process on Linux kernel space.<o:p></o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'><o:p> </o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'><o:p> </o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'>I was read some source code of postgres, like, <o:p></o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'>Postgres.C and others…<o:p></o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'> <o:p></o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'>I was found C instructions like Printf, that’s prohibitive > for Linux kernel applications, for example in kernel mode we use printk.<o:p></o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'><o:p> </o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'>I suppose that postgres are ported in a user space > only. I’m Ok?<o:p></o:p></span></font></p> That's correct. > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'><o:p> </o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'>Thanks <o:p></o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'>Moises<o:p></o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'><o:p> </o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'><o:p> </o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'><o:p> </o:p></span></font></p> > > <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size: > 10.0pt;font-family:Arial'>- <o:p></o:p></span></font></p> > > </div> > > </body> > > </html> You might want to consider using an email client that doesn't slobber: <p class=MsoNormal><font size=2 face=Arial><span lang=EN-GBstyle='font-size: 10.0pt;font-family:Arial'><o:p> </o:p></span></font></p> around everywhere. It's really irritating to have to read around that "deteriorata." -- (format nil "~S@~S" "cbbrowne" "ntlug.org") http://www3.sympatico.ca/cbbrowne/advocacy.html A cool feature of OOP is that the simplest examples are 500 lines. -- Peter Sestoft
Robert Hansen did a talk at OSCON on a compressed annealing framework called Djinni: <http://sixdemonbag.org/Djinni/> It's a framework to use compressed annealing (a derivative of simulated annealing) for finding approximate solutions to NP-complete problems such as the TSP with time windows. Note that while Djinni is implemented in C++, it already supports embedding via SWIG, and has a C wrapper and is accessible from other languages. And it's BSD-licensed... This has the potential to be an alternative to the present use of GEQO for query optimization for cases of large joins (e.g. - involving large numbers of tables). On the one hand, I'm somewhat suited to looking at this in that I have the operations research background to know what they're talking about. On the other hand, I'm not familiar with the optimizer, nor do I deal with sorts of cases with so many joins that this would be worthwhile. I've bounced a ToDo entry over to Bruce, and am making sure this is documented here on pgsql.hackers so that a web search can readily find it in the future... -- "cbbrowne","@","cbbrowne.com" http://www3.sympatico.ca/cbbrowne/ "It is far from complete, but it should explain enough that you don't just stare at your sendmail.cf file like a deer staring at an oncoming truck." -- David Charlap
moises wrote: > Hello, > > I’m new in postgres SQL and I have some questions about the space where > postgres process run. > > 1-Can any body say me what libs use postgres for make system calls, for > example LIBC? > > 2-Can any body talk me if some postgres process can run in Linux kernel > space? > > 3- Some body knows if exist some projects that ports postgres process on > Linux kernel space. > > > I was read some source code of postgres, like, > > Postgres.C and others… > > I was found C instructions like Printf, that’s prohibitive for Linux > kernel applications, for example in kernel mode we use printk. > > I suppose that postgres are ported in a user space only. I’m Ok? > > > Thanks > > Moises You can do it (e.g. http://www.yl.is.s.u-tokyo.ac.jp/~tosh/kml/) but why would you want to? PG runs fine in userspace and I can see no particular benefit to being in the kernel. What exactly are you trying to do with it? Are you trying to interface PG with some kernel facility? LL