Re: [ADMIN] postgresql and xfs filesystrem
Jaume: What about XFS performance on databases larger than 1 TB. We are successful running postgres on zfs with x4500 but I'm interested using commodity hardware. On Mon, Jan 26, 2009 at 2:34 AM, Jaume Sabater wrote: > On Mon, Jan 26, 2009 at 1:14 AM, Michael Monnerie > wrote: > > >> I did some benchmarking, now quite a while ago, which showed XFS to > >> be, for a totally write-bound workload, a *few* percent better than > >> ext3/JFS, but note that this is only a minor difference. > > XFS is a very active project and, in my opinion, the best filesystem > for UNIX. Apart from a nasty bug back in the second half of 2007 (if I > remember correctly), it's very reliable and fast. I've got more than a > dozen production servers running it since 2002 (aproximattely) and > I've never ever had a problem with it (no data loss, always an > outstanding performance, etc). I also have eight PostgreSQL servers > (8.1 and 8.3 versions) on XFS. As with everything, if you know how to > finetune it (and I would not call myself an expert on it), then you > get a performance boost. > > Regarding the benefits of XFS on PostgreSQL, I've come to the > conclusion that, the bigger the database and tables, the better. With > small databases with small tables, the difference in performance... > well, you won't notice it. But try a 30 GB... ;-) > > Still, all these "convictions" are very hard to prove. Hard as in > "very much time consuming". I've not run benchmarks in about 4 years, > to be honest, so I would understand you not taking my experience as > "reliable source of information" :-P > > -- > Jaume Sabater > http://linuxsilo.net/ > > "Ubi sapientas ibi libertas" > > -- > Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-admin > -- Ezra Taylor
[ADMIN] Recover with main/base files
Hello, I use postgresql 8.1 on a debian server with a /var JFS filesystem. After a crash of this FS (due to hardware instability: PSU), the /var/lib/postgresql/8.1/main folder was missing and its files were found under /var/lost+found. We have a full daily backup of this DB but I try to recover data from the morning it crashed. This is what I was able to recover : - main/base apparently without missing files ! - main/pg_xlog : I don't have these files names (but I can guess it from PG start errors) and I don't know in which order I've have to name them - main/pg_clog files and 0001 but not 0003 which I replaced with a zero padded file - main/pg_multixact - main/global/pg_control But the global folder content was not found. I probably have piece of it but I wasn't able to identify them except for pg_control. I tried to restore all the files over a base debian installation and then inserting a record in pg_database table like that : insert into pg_database (datname, datdba, encoding, datistemplate, datallowconn, datconnlimit, datlastsysoid, datvacuumxid, datfrozenxid, dattablespace) VALUES ( 'ex1', 10, 8, 'f', 't', -1, 10792, 499, 499, 1663); PG started without error and I can connect to the DB created but \dt show me nothing. Do you have alternatives to restore a db from main/base files ? If you have a method to reorder pg_xlog files, it interest me too. Thank you -- Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
Re: [ADMIN] postgresql and xfs filesystrem
On Mon, Jan 26, 2009 at 5:01 PM, Ezra Taylor wrote: >What about XFS performance on databases larger than 1 TB. We > are successful running postgres on zfs with x4500 but I'm interested using > commodity hardware. To be honest, I have never worked with databases that big :) -- Jaume Sabater http://linuxsilo.net/ "Ubi sapientas ibi libertas" -- Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
Re: [ADMIN] postgresql and xfs filesystrem
On Montag 26 Januar 2009 Ezra Taylor wrote: > What about XFS performance on databases larger than 1 TB. We > are successful running postgres on zfs with x4500 but I'm interested > using commodity hardware. See http://en.wikipedia.org/wiki/Xfs#Allocation_groups XFS was designed for big iron, where "big iron" from that time is commodity servers of today (4+ cores, 8GB+ RAM, RAID with lots of fast disks). During mkfs, you can decide how many allocation groups you want, and by the size of your partition, you decide how big a single AG is. And if your database spans lots of AGs, high parallelism can take place if it's well done. mfg zmi -- // Michael Monnerie, Ing.BSc- http://it-management.at // Tel: 0660 / 415 65 31 .network.your.ideas. // PGP Key: "curl -s http://zmi.at/zmi.asc | gpg --import" // Fingerprint: AC19 F9D5 36ED CD8A EF38 500E CE14 91F7 1C12 09B4 // Keyserver: wwwkeys.eu.pgp.net Key-ID: 1C1209B4 signature.asc Description: This is a digitally signed message part.
[ADMIN] finding dev rpms
I'm needing to installed psycopg2.. but I've hit a dependancy problem. pscycopg2 needs libpq stuff -- which is the the developer rpms. Trouble is I can only find developer rpms in yum repositories. So I went to install yum and found that since my red had is x86_64, yum croaks on importing cElementTree -- which it does have but won't import. Since yum wasn't really designed for RHEL -- it may not be worth it to try to resolve that issue, which leads me back to finding a downloadable rpm for the postgres developer packages; which I can't seem to locate at postgresql.org. Can anyone point me to postgresql 8.2 development rpms? or source? -- David Bear College of Public Programs at ASU 602-464-0424
Re: [ADMIN] finding dev rpms
On Mon, 2009-01-26 at 14:42 -0700, David Bear wrote: > I'm needing to installed psycopg2.. but I've hit a dependancy problem. > pscycopg2 needs libpq stuff -- which is the the developer rpms. > Trouble is I can only find developer rpms in yum repositories. So I > went to install yum and found that since my red had is x86_64, yum > croaks on importing cElementTree -- which it does have but won't > import. > > Since yum wasn't really designed for RHEL Yes it was. Just RHEL 5 and up. > Can anyone point me to postgresql 8.2 development rpms? or source? > Take a look at http://www.pgsqlrpms.org Joshua D. Drake -- PostgreSQL - XMPP: jdr...@jabber.postgresql.org Consulting, Development, Support, Training 503-667-4564 - http://www.commandprompt.com/ The PostgreSQL Company, serving since 1997 -- Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
