Re: [PERFORM] Several optimization options (config/hardware)
On 05/04/2012 09:57 AM, Albe Laurenz wrote: > Martin Grotzke wrote: >>> You could try different kernel I/O elevators and see if that >>> improves something. >>> >>> I have made good experiences with elevator=deadline and >>> elevator=noop. > >> Ok, great info. >> >> I'm not sure at which device to look honestly to check the current >> configuration. >> >> mount/fstab shows the device /dev/mapper/VG01-www for the relevant >> partition. When I check iostat high utilization is reported for >> the devices dm-4 and sda (showing nearly the same numbers for util >> always), >> so I suspect that dm-4 is mapped on sda. > > Use the option -N of "iostat" to see long device names. You can use > "lvm" to figure out the mapping. iostat with -N shows VG01-www for dm-4. For lvm/lvdisplay/dmsetup I get "Permission denied" as I have no root/sudo permissions. I need to check this with our hosting provider (hopefully we have a call today). >> This is the current config: $ cat /sys/block/sda/queue/scheduler >> noop anticipatory deadline [cfq] $ cat >> /sys/block/dm-4/queue/scheduler none > > Do you mean literal "none" or do you mean that the file is empty? "none" was the output of `cat /sys/block/dm-4/queue/scheduler`. >> Which of them should be changed? I'll discuss this also with our >> hosting provider next week, he'll know what has to be done. > > I'd just add "elevator=deadline" to the kernel line in > /etc/grub.conf and reboot. At least if it is a dedicated database > machine. > > But of course you want to change it on the fly first to test - not > knowing the answer to your question, I would change it in both > devices if I can. Ok, makes sense. Cheers, Martin signature.asc Description: OpenPGP digital signature
Re: [PERFORM] Result Set over Network Question
On Thu, May 3, 2012 at 5:40 PM, Merlin Moncure wrote: > On Thu, May 3, 2012 at 10:28 AM, Ronald Hahn, DOCFOCUS INC. > wrote: >> After some testing using wiershark (poor mans profiler) to see what was >> going on with the network I found that it was the tools I've been using. >> Both Aqua and PGadminIII have a large overhead per column to get the meta >> data. MSSQL sends that data upfront so the impact isn't as bad. I'm not sure >> if it's a limitation of the pgsql protocol vs tds or a limitation of Aqua or >> a combination of both. At any rate it turns out not to be part of the >> problem I'm having with my software stalling out so I'm back to Square one >> with my problem. So, Ronald, are you saying the different approach to meta data transfer is _not_ the issue? > ok, let's figure out what the issue is then. first, let's make sure > it isn't the server that's stalling: configure > log_min_duration_statement with an appropriate value so you start > catching queries that are taking longer then you think the should be. > also some client side logging directly wrapping the SQL invocation > couldn't hurt. is your application jdbc? Ronald said ODBC in his first posting. But since ADS seems to support JDBC as well trying that might be a good test to get another data point. Alternative tools for JDBC tests: http://squirrel-sql.sourceforge.net/ http://www.oracle.com/technetwork/developer-tools/sql-developer/overview/index.html Using the PG client remotely with "\timing on" might be an even better idea. Kind regards robert -- remember.guy do |as, often| as.you_can - without end http://blog.rubybestpractices.com/ -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
Re: [PERFORM] Result Set over Network Question
Robert Klemme, 07.05.2012 14:03: Alternative tools for JDBC tests: http://www.oracle.com/technetwork/developer-tools/sql-developer/overview/index.html SQL Developer does not support PostgreSQL This page: http://wiki.postgresql.org/wiki/Community_Guide_to_PostgreSQL_GUI_Tools also lists several JDBC based tools. Thomas -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
Re: [PERFORM] Result Set over Network Question
On Mon, May 7, 2012 at 2:11 PM, Thomas Kellerer wrote: > Robert Klemme, 07.05.2012 14:03: >> >> Alternative tools for JDBC tests: >> >> http://www.oracle.com/technetwork/developer-tools/sql-developer/overview/index.html > > SQL Developer does not support PostgreSQL Last time I checked (quite a while ago) you could use arbitrary JDBC drivers. There's also http://docs.oracle.com/cd/E25259_01/appdev.31/e24285/intro.htm#sthref306 And this seems to indicate that it's still the case: "[...] or another third-party driver. [...] JDBC URL (Other Third Party Driver): URL for connecting directly from Java to the database; overrides any other connection type specification." http://docs.oracle.com/cd/E25259_01/appdev.31/e24285/dialogs.htm#BACDGCIA I assume Oracle is not interested in aggressively advertizing this feature though. Kind regards robert -- remember.guy do |as, often| as.you_can - without end http://blog.rubybestpractices.com/ -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
Re: [PERFORM] Result Set over Network Question
Robert Klemme, 07.05.2012 15:44: http://www.oracle.com/technetwork/developer-tools/sql-developer/overview/index.html SQL Developer does not support PostgreSQL Last time I checked (quite a while ago) you could use arbitrary JDBC drivers. There's also http://docs.oracle.com/cd/E25259_01/appdev.31/e24285/intro.htm#sthref306 And this seems to indicate that it's still the case: "[...] or another third-party driver. [...] JDBC URL (Other Third Party Driver): URL for connecting directly from Java to the database; overrides any other connection type specification." http://docs.oracle.com/cd/E25259_01/appdev.31/e24285/dialogs.htm#BACDGCIA I assume Oracle is not interested in aggressively advertizing this feature though. That seems to be a documentation bug. I tried it, and it definitely does not work (or I am missing something). Their release notes at: http://www.oracle.com/technetwork/developer-tools/sql-developer/sqldev31-ea-relnotes-487612.html state: Third Party Databases SQL Developer supports IBM DB2 UDB LUW , Microsoft SQL Server and Microsoft Access, MySQL, Sybase Adaptive Server and Teradata. See Supported Platforms for details on all third party database releases supported. Regards Thomas -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
