RE: IDS9.4/AIX5.2 performace degradation

Dalibor You need to reconfigure the setting for the new hardware, new O/S, new RDBMS etc. etc. There is a vast difference between IDS 7 and IDS9 let alone the differences between Caldera and AIX !! Have you run UPDATE STATISTICS ? Keith -> -----Original Message----- -> From: Dalibor Krleza [mailto:dkrleza@yahoo.com] -> Sent: Thursday, July 22, 2004 1:00 PM -> To: informix-list@iiug.org -> Subject: IDS9.4/AIX5.2 performace degradation -> -> -> Hello everybody! -> -> Well, we are experiencing following problems: -> 1) Before migration to new system (server and operating system) we -> had installed IDS 7.31 database on Caldera operating system. -> -> 2) We migrated on IDS9.4 FC4, operating system AIX 5.2 on -> IBM pSeries server (p630). -> -> All configuration setting for database were copied to a new server. -> -> In meanwhile we are constantly experiencing significant performace -> degradation, like 4x slower than before. -> -> Any ideas?? -> -> Dalibor ********************************************************************************** This message is sent in strict confidence for the addressee only. It may contain legally privileged information. The contents are not to be disclosed to anyone other than the addressee. Unauthorised recipients are requested to preserve this confidentiality and to advise the sender immediately of any error in transmission. This footnote also confirms that this email message has been swept for the presence of computer viruses, however we cannot guarantee that this message is free from such problems. ********************************************************************************** sending to informix-list

Please go into your Onconfig and turn on your read_ahead. Set them to 128/120. Bounce the engine and try your runs again. "Simmons, Keith" <keith.simmons@office2office.biz> wrote in message news:<cdolj0$oo4$1@news.xmission.com>... > Dalibor > > You need to reconfigure the setting for the new hardware, new O/S, new RDBMS etc. etc. There is a vast difference between IDS 7 and IDS9 let alone the differences between Caldera and AIX !! > Have you run UPDATE STATISTICS ? > > Keith > > -> -----Original Message----- > -> From: Dalibor Krleza [mailto:dkrleza@yahoo.com] > -> Sent: Thursday, July 22, 2004 1:00 PM > -> To: informix-list@iiug.org > -> Subject: IDS9.4/AIX5.2 performace degradation > -> > -> > -> Hello everybody! > -> > -> Well, we are experiencing following problems: > -> 1) Before migration to new system (server and operating system) we > -> had installed IDS 7.31 database on Caldera operating system. > -> > -> 2) We migrated on IDS9.4 FC4, operating system AIX 5.2 on > -> IBM pSeries server (p630). > -> > -> All configuration setting for database were copied to a new server. > -> > -> In meanwhile we are constantly experiencing significant performace > -> degradation, like 4x slower than before. > -> > -> Any ideas?? > -> > -> Dalibor > > ********************************************************************************** > This message is sent in strict confidence for the addressee only. It may > contain legally privileged information. The contents are not to be disclosed > to anyone other than the addressee. Unauthorised recipients are requested > to preserve this confidentiality and to advise the sender immediately of any > error in transmission. > This footnote also confirms that this email message has been swept for the > presence of computer viruses, however we cannot guarantee that this message > is free from such problems. > ********************************************************************************** > > > sending to informix-list

On Fri, 23 Jul 2004 09:48:46 -0400, D. Rucker wrote: > Please go into your Onconfig and turn on your read_ahead. Set them to > 128/120. Bounce the engine and try your runs again. > AAAAHHHHH!!!! I'd recommend against such drastic numbers. Especially since the RAU is 99.99% with the current (default) configuration and there's lots of it going on. It's not turned off, just default configured! If the system is using singleton spindles, then yes, there is some justification for larger RA_ settings. However, with any decent RAID setup bringing multiple spindles, multiple controllers, and loads of cache into play, and especially given that the RAID subsystem is performing its own readahead to its cache (and if the drives are SCSI they are performing THEIR own readahead to their local caches) you can do just fine with VERY low RA_ values in the IDS configuration. I use 32/8 on some VERY big and VERY busy servers with very nice results. Of course that's with EMC/Clariion's, a GB of Clariion cache, 25 SCSI spindles per side of a RAID10 array, but you get the idea. Art S. Kagel