Re: SHMVIRTSIZE on 64 bits OS
Posted in 2003
Sorry I missed the 64bit part or was just asleep. Just tried my test program compiled in 64bit mode on Solaris 8 and it allowed me to allocate and attach about 12.7GB of shared memory which is appoximately the amount of free real memory on the machine (out of 24GB), there was 22GB free swap at the time. I don't remember from the original post, is the IDS version an F release or a U release? Art S. Kagel ----- Original Message ----- From: Kalpesh Ruparelia <Kalpesh.Ruparelia@ril.com> At: 9/30 0:24 > > Hello, > > As per the 64bits os architecture it should support memory structure more > than 4GB. As much as I know it takes values as (2 exponetial to (n-1) ) so > if os is of 32bits than it cann't support more than 2exponential 31 = 4GB. > So if we apply the same formula for 64 bits than it should support in tera > bytes. We had taken decision to go for 64 bits just becoz of memory > structure requirement of more than 4GB and thats why we had upgrade all > component os, database and sap of 64bits. > > Now question is the problem is at OS OR at database level (application will > not come in picture). > > As you are saying problem could be at OS level. I want to confirm one thing > is that 64bits INFORMIX supports memory structure more than 4GB. It should > but for that does any informix patches are require. Have you experience > informix of more than 4GB memory structure ? > Once you assure me that 64bits informix supports more than 4GB memory > structure than I will concentrate only on OS. > > I am also simultaneously trying to find out the same from sun and informix > side. > > > Thanks & Regards, > Kalpesh > > > > > > > > "ART KAGEL, > > BLOOMBERG/ 65E To: > Kalpesh.Ruparelia@ril.com > 55TH" cc: > > <KAGEL@bloomberg. Subject: Re: SHMVIRTSIZE on 64 > bits OS > net> Importance: Normal Sender's OU: > Reliance |------------------| > > | [ ] Confidential | > 09/29/2003 06:20 > |------------------| > PM > > > > > > > > > > The restriction is in the Solaris 5.8 kernel. The maximum shared memory > (sum of > the sizes of all attached shared blocks) that you can attach to a single > process it about 3.8GB. I have a test program that shows the problem. All > UNIXes have such a limit and it is different on each. > > Art S. Kagel > > ----- Original Message ----- > From: Kalpesh Ruparelia <Kalpesh.Ruparelia@ril.com> > At: 9/27 3:50 > > > Hello Sir, > > I have informix 5.8, informix 7.31FC6. > > We have 15GB RAM. > > Whenever I try to set size of SHMVIRTSIZE to more than 4GB informix is > not > > able to accept value for more > > 4194304. > > If I try to set value greater than 4GB for SHMVIRTSIZE it showing very > > small value something like default value. > > I would like to know is there any informix bug or restriction of the > > informix software. > > > > Can u pl help me how to utilise my memory for better response. > > > > Thanks & Regards > > Kalpesh > > > >