I need some expertise

Two quick questions (using HP 11.23 and Informix 11.5.FC3) we are trying to improve the speed of inserts into a table. If we split it into two dbspaces, would it be better to distribute the data using round robin or mod2 of a date time field? I was favoring the mod2 strategy to speed up selects on the table versus the round robins, but others are worried that the processing time for the mod 2 will make that solution slower than the round robin. Does the mod 2 make the processing that much slower? Second question, We have set up the connection manager in front of two hot-hot HDR databases. What is the limit of the number of connections the CM can handle? Is that a tunable value? Thanks! Kate Tomchik [ kate@iiug.org ] www.iiug.org International Informix Users Group Board of Directors A computer lets you make more mistakes faster than any invention in human history - with the possible exceptions of handguns and tequila. Mitch Ratliffe

kate wrote: > Two quick questions (using HP 11.23 and Informix 11.5.FC3) > > we are trying to improve the speed of inserts into a table. If we split it > into two dbspaces, would it be better to distribute the data using round > robin or mod2 of a date time field? > > I was favoring the mod2 strategy to speed up selects on the table versus the > round robins, but others are worried that the processing time for the mod 2 > will make that solution slower than the round robin. Does the mod 2 make > the processing that much slower? I don't think round robin will be materially quicker than mod 2. Are you sure, however, that the problem is not elsewhere? Like your logical log, for instance? > Second question, > We have set up the connection manager in front of two hot-hot HDR > databases. What is the limit of the number of connections the CM can > handle? Is that a tunable value? I didn't think there was any limit. I would, however, treat the CM as something which also needs some kind of failover. ;o) -- Cheers, Obnoxio The Clown http://obotheclown.blogspot.com I will now proceed to pleasure myself with this fish. -- This message has been scanned for viruses and dangerous content by OpenProtect(http://www.openprotect.com), and is believed to be clean.

Kate, Realistically the inserts will only speed up if the fragments for the table go to different disk controllers, otherwise you are still going through the same IO pathways to get to disk. If the inserts come in as a batch, then the table goes quiet for a while, maybe you could size the buffers large enough to capture the bulk of the incoming inserts? I would suggest only after ensuring that the buffers, logs (logical in particular), cleaners and LRU's aren't slowing the inserts down do you think about reorging the table. Jarrod Teale Team Lead - Manufacturing Execution Systems Automation & Process Control Group NZ Technical Fonterra -----Original Message----- From: ids-bounces@iiug.org [mailto:ids-bounces@iiug.org] On Behalf Of kate Sent: Tuesday, 24 November 2009 6:10 a.m. To: ids@iiug.org Subject: I need some expertise [18184] Two quick questions (using HP 11.23 and Informix 11.5.FC3) we are trying to improve the speed of inserts into a table. If we split it into two dbspaces, would it be better to distribute the data using round robin or mod2 of a date time field? I was favoring the mod2 strategy to speed up selects on the table versus the round robins, but others are worried that the processing time for the mod 2 will make that solution slower than the round robin. Does the mod 2 make the processing that much slower? Second question, We have set up the connection manager in front of two hot-hot HDR databases. What is the limit of the number of connections the CM can handle? Is that a tunable value? Thanks! Kate Tomchik [ kate@iiug.org ] www.iiug.org International Informix Users Group Board of Directors A computer lets you make more mistakes faster than any invention in human history - with the possible exceptions of handguns and tequila. Mitch Ratliffe ************************************************************************ ******* Forum Note: Use "Reply" to post a response in the discussion forum. DISCLAIMER: This email contains confidential information and may be legally privileged. If you are not the intended recipient or have received this email in error, please notify the sender immediately and destroy this email. You may not use, disclose or copy this email or its attachments in any way. Any opinions expressed in this email are those of the author and are not necessarily those of the Fonterra Co-operative Group. http://www.fonterra.com/

There is no limit on the number of connections CM can handle, so, there is no tunable parameter for CM. - Nilesh - ids-bounces@iiug.org wrote on 11/23/2009 11:10:29 AM: > From: > > "kate" <kate@iiug.org> > > To: > > ids@iiug.org > > Date: > > 11/23/2009 11:11 AM > > Subject: > > I need some expertise [18184] > > Sent by: > > ids-bounces@iiug.org > > Two quick questions (using HP 11.23 and Informix 11.5.FC3) > > we are trying to improve the speed of inserts into a table. If we split it > into two dbspaces, would it be better to distribute the data using round > robin or mod2 of a date time field? > > I was favoring the mod2 strategy to speed up selects on the table versus the > round robins, but others are worried that the processing time for the mod 2 > will make that solution slower than the round robin. Does the mod 2 make > the processing that much slower? > > Second question, > We have set up the connection manager in front of two hot-hot HDR > databases. What is the limit of the number of connections the CM can > handle? Is that a tunable value? > > Thanks! > Kate Tomchik [ kate@iiug.org ] www.iiug.org > International Informix Users Group Board of Directors > > A computer lets you make more mistakes faster than any invention in human > history - with the possible exceptions of handguns and tequila. > Mitch Ratliffe > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. >

Answers: 1 - For insert speed go with round robin. But it's not the MOD function that will slow you down, it's the YEAR(), MONTH(), DAY(), etc. function you'll need to extract the part of the DATETIME that you want to MOD on that will do it. They are not fast in my experience. 2 - The Connection Manager ONLY coordinates connections for the sessions that are actively seeking a new connection to a server, so they can effectively handle many many live connections since once the CM suggests the server that the session's library should connect to it is out of the loop. Art Art S. Kagel Oninit (www.oninit.com) IIUG Board of Directors (art@iiug.org) Disclaimer: Please keep in mind that my own opinions are my own opinions and do not reflect on my employer, Oninit, the IIUG, nor any other organization with which I am associated either explicitly or implicitly. Neither do those opinions reflect those of other individuals affiliated with any entity with which I am affiliated nor those of the entities themselves. On Mon, Nov 23, 2009 at 12:10 PM, kate <kate@iiug.org> wrote: > Two quick questions (using HP 11.23 and Informix 11.5.FC3) > > we are trying to improve the speed of inserts into a table. If we split it > into two dbspaces, would it be better to distribute the data using round > robin or mod2 of a date time field? > > I was favoring the mod2 strategy to speed up selects on the table versus > the > round robins, but others are worried that the processing time for the mod 2 > will make that solution slower than the round robin. Does the mod 2 make > the processing that much slower? > > Second question, > We have set up the connection manager in front of two hot-hot HDR > databases. What is the limit of the number of connections the CM can > handle? Is that a tunable value? > > Thanks! > Kate Tomchik [ kate@iiug.org ] www.iiug.org > International Informix Users Group Board of Directors > > A computer lets you make more mistakes faster than any invention in human > history - with the possible exceptions of handguns and tequila. > Mitch Ratliffe > > > > ******************************************************************************* > Forum Note: Use "Reply" to post a response in the discussion forum. > > --00151747b74a12fd610479122ad0