[HACKERS] SoC Ideas for people looking for projects
Hi, If you are looking for a SoC idea, I have listed a couple below. I am not sure how good of an idea they are but I have ran into the following limitations and probably other people have as well in the past. 1. Can user based priorities be implemented as a summer project? To some extent it has already been implemented in research (http:// www.cs.cmu.edu/~bianca/icde04.pdf), so it is definitely possible and scalable. 2. Distributed full-text indexing. This one I am really not sure how possible it is but (TSearch2) very scalable (cannot do multi terabyte fulltext indexes). Maybe some sort system could be devised to perform fulltext searches over multiple systems and merge the ranked results at some root node. Benjamin On Mar 20, 2007, at 10:07 AM, Josh Berkus wrote: Students Professors, There are only 5 days left to submit your PostgreSQL Google Summer of Code Project: http://www.postgresql.org/developer/summerofcode.html If you aren't a student, but know a CS student interested in databases, testing, GUIs, or any other OSS coding, please point them to our SoC page and encourage them to apply right away! If you are a student, and you've been trying to perfect your application, please go ahead and submit it ... we can't help you if you miss the deadline, but we can help you fix an incomplete application. --Josh Berkus ---(end of broadcast)--- TIP 2: Don't 'kill -9' the postmaster ---(end of broadcast)--- TIP 2: Don't 'kill -9' the postmaster
[HACKERS] SoC Ideas for people looking for projects
Hi, If you are looking for a SoC idea, I have listed a couple below. I am not sure how good of an idea they are but I have ran into the following limitations and probably other people have as well in the past. 1. Can user based priorities be implemented as a summer project? To some extent it has already been implemented in research (http:// www.cs.cmu.edu/~bianca/icde04.pdf), so it is definitely possible and scalable. 2. Distributed full-text indexing. This one I am really not sure how possible it is but (TSearch2) very scalable (cannot do multi terabyte fulltext indexes). Maybe some sort system could be devised to perform fulltext searches over multiple systems and merge the ranked results at some root node. Benjamin On Mar 20, 2007, at 10:07 AM, Josh Berkus wrote: Students Professors, There are only 5 days left to submit your PostgreSQL Google Summer of Code Project: http://www.postgresql.org/developer/summerofcode.html If you aren't a student, but know a CS student interested in databases, testing, GUIs, or any other OSS coding, please point them to our SoC page and encourage them to apply right away! If you are a student, and you've been trying to perfect your application, please go ahead and submit it ... we can't help you if you miss the deadline, but we can help you fix an incomplete application. --Josh Berkus ---(end of broadcast)--- TIP 2: Don't 'kill -9' the postmaster ---(end of broadcast)--- TIP 4: Have you searched our list archives? http://archives.postgresql.org
Re: [HACKERS]
What kind of performance difference can be expected between Linux and Windows? Benjamin Arai [EMAIL PROTECTED] [EMAIL PROTECTED] http://www.benjaminarai.com -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Magnus Hagander Sent: Tuesday, February 15, 2005 10:03 AM To: E.Rodichev Cc: pgsql-hackers@postgresql.org; oleg@sai.msu.su Subject: Re: [HACKERS] I've tested the performance of 8.0.1 at my dual-boot notebook (Linux and Windows XP). I installed 8.0.1 for Linux and Windows XP, and run pgbench -c 1 -t 1000 Under Linux (kernel 2.6.10) I got about 800 tps, and under Windows XP - about 20-24 tps. Next I switched off virtual memory under Windows (as it was recommended in posting http://www.pgsql.ru/db/mw/msg.html?mid=2026070). It does not help. Without virtual memory I got 15-17 tps. Question 1: Is your writeback cache really disabled in Linux, on the harddrive? Windows fsync will *write through the disk write cache* if the driver is properly implemented. AFAIK, on Linux if write cache is enabled on the drive, fsync will only get into the cache. Difficult to say concerning writeback cache... I have 2.6.10 without any additional tuning, file system is ext2. From dmesg: hda: TOSHIBA MK8026GAX, ATA DISK drive hda: max request size: 128KiB hda: 156301488 sectors (80026 MB), CHS=65535/16/63, UDMA(100) hda: cache flushes supported Run: hdparm -I /dev/hda If you get a line like: Commands/features: Enabled Supported: *READ BUFFER cmd *WRITE BUFFER cmd *Host Protected Area feature set *Look-ahead *Write cache ... (last line is what matters here) you have write cacheing enabled. To turn it of, run hdparm -W0 /dev/hda Not sure if you need to reboot, I don'tt hink so. Then re-run the benchmark on linux. 800tps sounds unreasonably high on a notebook. Yes, I also was surprized. The same test at Xeon 2.4GHz server indicates about 700 tps. But it is another issue. The CPU probably has nothing to do with this, it's probably all I/O. Question 2: Please try disabling the stats connector and see if that helps. Merlin Moncure reported some scalability issues with the stats collector previously. Sorry, what is stats connector? That's supposed to be stats collector, as you realised in your other mail. Sorry. Several yeas ago (about 1997-1998) Oleg Bartunov and me had the same performance results (Linux vs Windows NT + cygwin). It was the discussion at this list with resume that the reason is the implementation of shared memory under Windows. Every IPC operation results the HDD access. It shouldn't in 8.0 - at least not on the native win32. Don't know about cygwin. Yes, I also expected that the performance for native implementation will be more reasonable. In fact, during pgbench test under Windows and under Linux HDD LED lights continiously, so looks like under Windows there are much more disk operations compared with Linux. That would be consistent with the theory that write-back caching is enabled on linux and not on windows. //Magnus ---(end of broadcast)--- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly ---(end of broadcast)--- TIP 6: Have you searched our list archives? http://archives.postgresql.org
[HACKERS] Status of PostgreSQL for 4+ processors
I have been trying to find information on PostgreSQL for running it on greater then 4 processors. Are there any benchmarks out there and have there been any problems or does anybody forsee any issues running PostgreSQL with more then 4 processors? Benjamin ---(end of broadcast)--- TIP 9: the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match
[HACKERS] Goals for 8.1
What are the goals for 8.1? ---(end of broadcast)--- TIP 2: you can get off all lists at once with the unregister command (send unregister YourEmailAddressHere to [EMAIL PROTECTED])
[HACKERS] PostgreSQL Specification
I asked this question a while back and I got an answer but I lost it. Where can I get a copy of the SQL specification that PostgreSQL follows? Who ever answered, as I recall said it was not free if that is any help. Benjamin
[HACKERS] Has anybody tried porting PostgreSQL to a stack machine or accumulator machine?
Has anybody tried porting PostgreSQL to a stack machine or accumulator machine? More specifically, how specialized is the source code in PostgreSQL, would it be possible to port the PostgreSQL source to a older version of GCC? There are some stack and accumulator based machines that contain stripped down versions of GCC, so I am trying to figure out if I should attempt to port the source or if its not possible. Benjamin Arai [EMAIL PROTECTED] ---(end of broadcast)--- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faqs/FAQ.html
[HACKERS] Where do I get the spec for PostgreSQL
Where can I obtain a spec for postgresql, so I can start looking at the code? Benjamin [EMAIL PROTECTED] ---(end of broadcast)--- TIP 8: explain analyze is your friend
