Red Hat / Suse / Informix 10 / 2 Gb

Hi folks, I´m trying to wake up a informix instance on SUSE ( and Red Hat too ). They are 32 BITS OS both. Is there a memory alocation limit to those plataforms? May I use more than 2 Gb in my shared memory alocation? Thanks, André Luiz _________________________________________________________________ Veja só alguns dos novos serviços online no Windows Live Ideas — são tão novos que ainda não foram disponibilizados oficialmente. http://ideas.live.com

Yes, you can grab more than 2 GB. I am grabbing 22 GB on Red Hat 4 currently. You will have to modify the kernel memory settings to accomplish that. Mine are set at the following: # Controls the maximum shared segment size, in bytes # kernel.shmmax = 22548578304 # Controls the maximum number of shared memory segments, in pages # kernel.shmall = 8388608 # Controls the maximum number of shared memory segments # kernel.shmmni = 8192 Lennie -----Original Message----- From: ids-bounces@iiug.org [mailto:ids-bounces@iiug.org]On Behalf Of Andr Luiz Rufino Sent: Thursday, April 19, 2007 8:22 AM To: ids@iiug.org Subject: Red Hat / Suse / Informix 10 / 2 Gb [8971] Hi folks, I´m trying to wake up a informix instance on SUSE ( and Red Hat too ). They are 32 BITS OS both. Is there a memory alocation limit to those plataforms? May I use more than 2 Gb in my shared memory alocation? Thanks, André Luiz _________________________________________________________________ Veja só alguns dos novos serviços online no Windows Live Ideas - são tão novos que ainda não foram disponibilizados oficialmente. http://ideas.live.com **************************************************************************** *** Forum Note: Use "Reply" to post a response in the discussion forum.

Take a look to Linux Kernel 2.6.x configuration. Shared Memory related kernel parameters are defined in /proc/sys/kernel: /proc/sys/kernel/shmmax max size of a Shared Memory Segment in Byte recommendation 2GB: 2147483648 /proc/sys/kernel/shmall total sum of Shared Memory in 4kB Pages recommendation for 16GB Memory: 4194304 /proc/sys/kernel/shmmni total sum of Shared Memory Segments recommendation (Linux default): 4096 cat /proc/sys/kernel/<parameter> Example: cat /proc/sys/kernel/shmmax Set values of kernel parameter dynamically: echo <value> > /proc/sys/kernel/<parameter> Example: echo 2147483648 > /proc/sys/kernel/shmmax Set values permanent in /etc/sysctl.conf kernel.<parameter> = <value> Example: kernel.shmmax = 2147483648 32bit Linux (i686) limits the Virtual Memory of 4GB to 3GB for one application. The rest of 1GB is reserved for the kernel. An exception is the optional hugemem kernel of RHEL 4: 4GB Virtual Memory is addressable. 64bit Linux (x86_64) is able to address almost 512GB (RHEL 4) or 131072GB (SLES 10) Virtual Memory. The amount of Virtual Memory addressable as Shared Memory is restricted by Binaries (Text und Heap), Shared Libraries and Stack. They are located at different regions on different Linux distributions. The used regions can be checked in file /proc/<ProcessID>/maps of a given process, e.g.: - detect ProcessID (pid #) of CPU VP (class cpu): onstat -g glo vp pid class usercpu syscpu total 1 18303 cpu 3.48 0.20 3.68 - list regions (maps) of Virtual Memory: cat /proc/18303/maps IDS Shared Memory requires one big, continuous (not interrupted) free region in the Virtual Memory. The starting address of this region is defined in ONCONFIG parameter SHMBASE. RHEL 4 (i686) ------------- Virtual Memory: 0x00000000 - 0xbfffffff Shared Libraries: 0x00000000 -> Binaries: 0x08000000 -> Stack: <- 0xbfffffff free space: 0x10000000 - 0xafffffff SHMBASE 0x10000000L # provides 2,5GB Shared MemoryUsing UDRs and Datablades loads Shared Libraries at Adress 0x00000000 ascending. Change of SHMBASE 0x10000000L may be required, e.g. to 0x40000000L RHEL 4 (i686), hugemem Kernel ----------------------------- Virtual Memory: 0x00000000 - 0xffffffff Shared Libraries: 0x00000000 -> Binaries: 0x08000000 -> Stack: <- 0xffffffff free space: 0x10000000 - 0xefffffff SHMBASE 0x10000000L # provides 3,5GB Shared MemoryUsing UDRs and Datablades loads Shared Libraries at Adress 0x00000000 ascending. Change to a higher value of SHMBASE 0x10000000L may be required. SLES 10 (i686) -------------- Virtual Memory: 0x00000000 - 0xbfffffff Binaries: 0x08000000 -> Shared Libraries: <- 0xb7ffffff Stack: <- 0xbfffffff free Space: 0x10000000 - 0xafffffff SHMBASE 0x10000000L # provides 2,5GB Shared Memory Shared Libraries are loaded at address 0xb7ffffff descending . Collisions of IDS Shared Memory Segments with Shared Libraries must be avoided. RHEL 4 (x86_64) --------------- Virtual Memory: 0x0000000000 - 0x7fbfffffff Binaries: 0x0000000000 -> Shared Libraries: 0x2a95556000 -> 0x322ee00000 -> Stack: <- 0x7fbfffffff Big free spaces: 0x0010000000 - 0x2a8fffffff 0x3240000000 - 0x7fafffffff SHMBASE 0x0010000000L # provides 170GB Shared Memory SHMBASE 0x3240000000L # provides 309GB Shared Memory Shared Libraries in the example are loaded at address 0x322ee00000 ascending. A higher value of SHMBASE 0x3240000000L may be required. SLES 10 (x86_64) ---------------- Virtual Memory: 0x000000000000 - 0x7fffffffffff Binaries: 0x000000000000 -> Shared Libraries: 0x2a0000000000 -> Stack: <- 0x7fffffffffff Big free spaces: 0x000010000000 - 0x29ffffffffff 0x2c0000000000 - 0x7fffa0000000 SHMBASE 0x000010000000L # provides 43000GB Shared Memory SHMBASE 0x2c0000000000L # provides 86000GB Shared Memory Shared Libraries are loaded at address 0x2a0000000000 ascending. A higher value of SHMBASE 0x2c0000000000L may be required. Andreas On Thursday 19 April 2007 15:21, André Luiz Rufino wrote: > Hi folks, > > I´m trying to wake up a informix instance on SUSE ( and Red Hat too > ). They are 32 BITS OS both. Is there a memory alocation limit to > those plataforms? May I use more than 2 Gb in my shared memory > alocation? > > Thanks, > > André Luiz > _________________________________________________________________ > Veja só alguns dos novos serviços online no Windows Live Ideas — > são tão novos que ainda não foram disponibilizados oficialmente. > http://ideas.live.com > > > ********************************************************************* >********** Forum Note: Use "Reply" to post a response in the > discussion forum. -- Andreas Breitfeld; Informix Development Munich IBM Deutschland GmbH; Vorsitzender des Aufsichtsrats: Hans Ulrich Maerki; Geschäftsführung: Martin Jetter (Vorsitzender), Rudolf Bauer, Christian Diedrich, Christoph Grandpierre, Matthias Hartmann, Andreas Kerstan; Sitz der Gesellschaft: Stuttgart; Registergericht: Amtsgericht Stuttgart, HRB 14562; WEEE-Reg.-Nr. DE 99369940