Does this mean that I should change my udtconfig parameter to 10485760 * 4 and performance may increase? - Rod
$UDTBIN/ipcstat -mb | grep sbcs m 8107 0 --rw-r--r-- root other 10485760 -> sbcs R6.0 m 37971309 0 --rw-r--r-- root other 10485760 -> sbcs R6.0 m 3367268 0 --rw-r--r-- root other 10485760 -> sbcs R6.0 m 165791808 0 --rw-r--r-- root other 10485760 -> sbcs R6.0 -----Original Message----- From: Wally Terhune [mailto:[EMAIL PROTECTED] Sent: Thursday, May 26, 2005 6:02 PM To: [email protected] Subject: RE: [U2] udtconfig gurus - AIX shm tuning AIX doc hasn't been updated (though it is overdue...) If you read it, don't use AIX extended shared memory - performance issues with how UniData uses shared memory and how extended shared memory is implemented by AIX. We do have a 64-bit port of UniData for AIX (UniData 6.1.7)- which makes all of the 32-bit shared memory restrictions disappear. If you are running a 32-bit port of UniData (all the rest) - here is the short version of tuning to avoid shared memory errors: 1) Set SHM_ATT_ADD=0 (if not already) 2) Tune so you only need one glm segment (record lock table - GLM_MEM_SEGSZ) ($UDTBIN/ipcstat -mb | grep glm on a busy system) 3) Tune so you only need one sbcs segment (SBCS_SHM_SIZE) - depends on how many application programs you globally catalog 4) SHM_GNPAGES=64, SHM_GPAGESZ=2048 - reasonable place to start. Make sure pages*pagesz*512 does not exceed 256mb. 5) SHM_LMINENTS=15 (or more - small structure - 30 is OK setting and likely more than you will ever need). Wally Terhune Manager - U2 Advanced Technical Services IBM Information Management Solutions Tel: 303.294.4866 Fax: 303.294.4832 [EMAIL PROTECTED] www.ibm.com/software/data/u2/support - Open, Query, Update, Search - Online! "Ken Wallis" <[EMAIL PROTECTED] node.on.net> To Sent by: <[email protected]> [EMAIL PROTECTED] cc stserver.u2ug.org Subject RE: [U2] udtconfig gurus? 05/26/2005 04:29 PM Please respond to u2-users Robert Paterson wrote: > Have to say that the best source of that information in my view is the > UniData manuals. >earlier Jeff Schoby wrote: > >> Does anyone have a good detailed reference for the settings in the >> udtconfig file and the formulas used to set each parameter. >> Or at least some good rules of thumb? >> >> I'm migrating from an AIX 4.3.3 box with 1.25GB of ram (and about 150 >> users) to a p5 Series running aix 5.3 with 12GB of ram and I want to >> make sure we make efficient use of that ram. I'd have to say I agree with Robert. The best available source is the manuals, and these are online, but since Jeff doesn't indicate version numbers for UniData, it s hard to provide the right URL. Also, there is a document specifically about tuning UniData on AIX because of the special constraints that OS used to impose. I have a copy of this, but don't know if there is an updated version available now AIX has moved forward so far. Wally? If there isn't a more readily available version of this document, then I'll happily email it direct to you Jeff, but you'll need to understand how AIX has changed lately so you can determine which bits are now less important. AIX 4.3.3 to 5.3 in one bound is a big jump. Are you keeping the same UniData Release? Or is this a move to a new box that happens to have a new OS release? Do you use RFS or Journaling? Replication, ODBC? All these might make demands on how you set up your udtconfig. If you'd like professional input on tuning the new system, then I'm sure there are guys in the US who offer consulting services and have experience with this. IBM do it, I know, and I think Strategy 7 do too. Alternatively, if you can provide me with access to the system remotely, then I'd be prepared to give you my input on a professional basis too. Drop me a direct email if you want to follow up on this. Cheers, Ken Ken Wallis Empower Data Solutions Blue Mountains, Sydney, Australia ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/ [demime 1.01d removed an attachment of type image/gif which had a name of graycol.gif] [demime 1.01d removed an attachment of type image/gif which had a name of pic24344.gif] [demime 1.01d removed an attachment of type image/gif which had a name of ecblank.gif] ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/ ------- u2-users mailing list [email protected] To unsubscribe please visit http://listserver.u2ug.org/
